1
NBME 25
NBME 25 FINAL EXAM (NEW 2025/ 2026
UPDATE) QUESTIONS & ANSWERS| GRADE A|
100% CORRECT (VERIFIED SOLUTION)
Exam Section 1: Item 1 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
A 66-year-old man has a surgical excision of a brain mass; a photomicrograph of
excised tissue is shown. He has smoked 1 pack of cigarettes daily for the past 50
years. His blood pressure is 130/90 mm Hg.
Laboratory studies show polycythemia, hypercalcemia, and microscopic hematuria.
Immunostaining of the tissue is positive for epithelial membrane antigen and
negative for carcinoembryonic antigen. Which of
the following is the most likely site of the primary neoplasm?
O A) Colon
B) Kidney
C) Liver
D) Lung
E) Lymph node
O F) Prostate
G) Testis
Correct Answer: B.
Renal cell carcinoma (RCC) is an adenocarcinoma of tubular epithelial cells. RCC is
the most common primary malignancy of the kidney and most commonly occurs in
older, male smokers. It can present with gross or microscopic hematuria, flank pain,
we -
Exam Section 1: Item 2 of 50
Național Board of Medical Examiners®
Comprehensive Basic Science Self-Assessment
8. In a study designed to test the effectiveness of a new drug in the treatment of
endometriosis, 100 women are randomly assigned to one of two groups: 48 of the
women receive the new drug and 52 receive standard therapy. Which of the
following is the
major benefit of assigning patients in this manner?
O A) The effect of confounding variables is decreased
B) The likelihood of achieving statistical significance is increased
C) The power of the study is increased
NBME 25
, 2
NBME 25
D) The study groups are equalized
Correct Answer: A.
When conducting a study, there are many potential biases that could impact the
results and lead the investigators to erroneously reject the null hypothesis. One such
bias is confounding bias, in which an unmeasured characteristic differs between two
groups of
subjects and causes a difference in out -
Exam Section 1: Item 3 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
. A 17-year-old girl who is a gymnast is brought to the emergency department 30
minutes after fainting during a competition. Her mother says that the patient eats so
little food that her teeth are decaying and that she has stopped menstruating. She is
165 cm
(5 ft 5 in) tall and weighs 37 kg (82 lb); BMI is 14 kg/m2. Sexual development is
Tanner stage 2. Her pulse is 130/min and blood pressure is 80/50 mm Hg. Physical
examination shows pale, cool skin. There are scars across her knuckles that she
says are cat
scratches. Serum studies show a potassium concentration of 2.9 mEq/L and a
chloride concentration of 92 mEq/L. Which of the following is the most likely
diagnosis?
A) Anorexia nervosa (binge eating/purging type)
B) Anorexia nervosa (restricting type)
C) Bulimia nervosa (nonpurging type)
D) Chronically -
Exam Section 1: Item 4 of 50
Național Board of Medical Examiners®
Comprehensive Basic Science Self-Assessment
10. A fetus exposed to an infection at 22 weeks' gestation appears normal at birth
but later develops a persistent mucopurulent nasal discharge, malformed teeth, skin
cracks and fissures around oral, anal, and vulvar orifices, splenomegaly, and
lymphadenopathy. Which of the following best explains these findings?
A) Inability of maternal rubella antibodies to cross the placental barrier
O B) Increased amounts of herpes simplex virus in amniotic fluid
O C) Maternal failure to generate antibodies to cytomegalovirus
D) Maternally transferred spirochetes replicating in fetal tissue
E) Persistence of HIV in placental tissue
Correct Answer: D.
Congenital syphilis is caused by the maternal transfer of Treponema pallidum
spirochetes through the placenta in the second and third trimesters, which then
replicate in -
NBME 25
, 3
NBME 25
Exam Section 1: Item 5 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
. The biological effects of thyroid hormone and retinoic acid are mediated through
similar mechanisms. Which of the following properties is common to the receptors for
these two compounds?
A) Ability to activate phospholipase C
B) DNA-binding domain
C) Formation of a dimer on binding of hormone
D) Interaction with a G protein
E) Tyrosine kinase activity
Correct Answer: B.
The receptors for retinoic acid and thyroid hormone are both nuclear receptors that
contain DNA-binding domains. Nuclear receptors can initially be located in either the
cytosol or nucleus. They bind to hormones which are either lipophilic and therefore
capable of
diffusion across the outer cell membrane, or which are transported into the cell via
carrier-mediated transport. Once nuclear receptors bind their respective hormones,
they tr -
12
Exam Section 1: Item 12 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
12. A 57-year-old man comes to the physician because of an intermittent cough and
a 9-kg (20-lb) weight loss over the past 6 months. He has smoked 1 pack of
cigarettes daily for 42 years. His serum calcium concentration is 13.3 mg/dL. An x-
ray of the chest
shows a 4-cm central mass in the left lung. Which of the following is the most likely
diagnosis?
A) Adenocarcinoma of the lung
B) Large cell lymphoma
C) Metastatic osteosarcoma
D) Metastatic renal cell carcinoma
E) Small cell carcinoma of the lung
F) Squamous cell carcinoma of the lung
Correct Answer: F.
Squamous cell carcinoma of the lung is the second most common type of primary
lung cancer after adenocarcinoma. Risk factors for all major types of lung cancer
include tobacco use, secondhand smoke, asbestos, or radon exposure, and a family
history of lu -
13
Exam Section 1: Item 13 of 50
Național Board of Medical Examiners®
NBME 25
, 4
NBME 25
Comprehensive Basic Science Self-Assessment
13. A 45-year-old woman has had progressive fatigue and mild shortness of breath
with exertion during the past 3 months. She thinks she had rheumatic fever at the
age of 10 years. A grade 2/6, rumbling, diastolic murmur is heard at the fifth left
intercostal
space in the midclavicular line. A lateral x-ray of the chest shows mild posterior
displacement of the esophagus. Which of the following cardiovascular structures is
most likely responsible for the esophageal displacement?
O A) Descending aorta
B) Left atrium
C) Left ventricle
D) Right atrium
E) Right ventricle
Correct Answer: B.
In the typical anatomic orientation, the left atrium is the most posterior part of the
heart and lies anterior to the esophagus in the mediastinum. In this patient, the left
atrium is most likely enlarged secondary to mitral -
14
Exam Section 1: Item 14 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
14. A 34-year-old woman is brought to the emergency department by her husband
because of an inability to see objects in the peripheral visual fields in both eyes for 1
day. Her temperature is 37.2°C (99°F), pulse is 68/min, respirations are 16/min, and
blood
pressure is 124/78 mm Hg. Automated computerized perimetry examination shows a
loss of the temporal visual field in both eyes. Neurologic examination shows no other
abnormalities. This patient is most likely to have which of the following additional
findings?
A) Amenorrhea
B) Aphasia
C) Double vision
D) Loss of memory
E) Seizures
Correct Answer: A.
This patient's bitemporal hemianopsia is most likely the result of optic chiasm
compression from a pituitary adenoma, which is often associated with amenorrhea in
women secondary to the overproduction of pro -
15
Exam Section 1: Item 15 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
15. A 46-year-old man with type 2 diabetes mellitus is brought to the emergency
department by his wife 30 minutes after he developed chest pain and then lost
NBME 25
NBME 25
NBME 25 FINAL EXAM (NEW 2025/ 2026
UPDATE) QUESTIONS & ANSWERS| GRADE A|
100% CORRECT (VERIFIED SOLUTION)
Exam Section 1: Item 1 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
A 66-year-old man has a surgical excision of a brain mass; a photomicrograph of
excised tissue is shown. He has smoked 1 pack of cigarettes daily for the past 50
years. His blood pressure is 130/90 mm Hg.
Laboratory studies show polycythemia, hypercalcemia, and microscopic hematuria.
Immunostaining of the tissue is positive for epithelial membrane antigen and
negative for carcinoembryonic antigen. Which of
the following is the most likely site of the primary neoplasm?
O A) Colon
B) Kidney
C) Liver
D) Lung
E) Lymph node
O F) Prostate
G) Testis
Correct Answer: B.
Renal cell carcinoma (RCC) is an adenocarcinoma of tubular epithelial cells. RCC is
the most common primary malignancy of the kidney and most commonly occurs in
older, male smokers. It can present with gross or microscopic hematuria, flank pain,
we -
Exam Section 1: Item 2 of 50
Național Board of Medical Examiners®
Comprehensive Basic Science Self-Assessment
8. In a study designed to test the effectiveness of a new drug in the treatment of
endometriosis, 100 women are randomly assigned to one of two groups: 48 of the
women receive the new drug and 52 receive standard therapy. Which of the
following is the
major benefit of assigning patients in this manner?
O A) The effect of confounding variables is decreased
B) The likelihood of achieving statistical significance is increased
C) The power of the study is increased
NBME 25
, 2
NBME 25
D) The study groups are equalized
Correct Answer: A.
When conducting a study, there are many potential biases that could impact the
results and lead the investigators to erroneously reject the null hypothesis. One such
bias is confounding bias, in which an unmeasured characteristic differs between two
groups of
subjects and causes a difference in out -
Exam Section 1: Item 3 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
. A 17-year-old girl who is a gymnast is brought to the emergency department 30
minutes after fainting during a competition. Her mother says that the patient eats so
little food that her teeth are decaying and that she has stopped menstruating. She is
165 cm
(5 ft 5 in) tall and weighs 37 kg (82 lb); BMI is 14 kg/m2. Sexual development is
Tanner stage 2. Her pulse is 130/min and blood pressure is 80/50 mm Hg. Physical
examination shows pale, cool skin. There are scars across her knuckles that she
says are cat
scratches. Serum studies show a potassium concentration of 2.9 mEq/L and a
chloride concentration of 92 mEq/L. Which of the following is the most likely
diagnosis?
A) Anorexia nervosa (binge eating/purging type)
B) Anorexia nervosa (restricting type)
C) Bulimia nervosa (nonpurging type)
D) Chronically -
Exam Section 1: Item 4 of 50
Național Board of Medical Examiners®
Comprehensive Basic Science Self-Assessment
10. A fetus exposed to an infection at 22 weeks' gestation appears normal at birth
but later develops a persistent mucopurulent nasal discharge, malformed teeth, skin
cracks and fissures around oral, anal, and vulvar orifices, splenomegaly, and
lymphadenopathy. Which of the following best explains these findings?
A) Inability of maternal rubella antibodies to cross the placental barrier
O B) Increased amounts of herpes simplex virus in amniotic fluid
O C) Maternal failure to generate antibodies to cytomegalovirus
D) Maternally transferred spirochetes replicating in fetal tissue
E) Persistence of HIV in placental tissue
Correct Answer: D.
Congenital syphilis is caused by the maternal transfer of Treponema pallidum
spirochetes through the placenta in the second and third trimesters, which then
replicate in -
NBME 25
, 3
NBME 25
Exam Section 1: Item 5 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
. The biological effects of thyroid hormone and retinoic acid are mediated through
similar mechanisms. Which of the following properties is common to the receptors for
these two compounds?
A) Ability to activate phospholipase C
B) DNA-binding domain
C) Formation of a dimer on binding of hormone
D) Interaction with a G protein
E) Tyrosine kinase activity
Correct Answer: B.
The receptors for retinoic acid and thyroid hormone are both nuclear receptors that
contain DNA-binding domains. Nuclear receptors can initially be located in either the
cytosol or nucleus. They bind to hormones which are either lipophilic and therefore
capable of
diffusion across the outer cell membrane, or which are transported into the cell via
carrier-mediated transport. Once nuclear receptors bind their respective hormones,
they tr -
12
Exam Section 1: Item 12 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
12. A 57-year-old man comes to the physician because of an intermittent cough and
a 9-kg (20-lb) weight loss over the past 6 months. He has smoked 1 pack of
cigarettes daily for 42 years. His serum calcium concentration is 13.3 mg/dL. An x-
ray of the chest
shows a 4-cm central mass in the left lung. Which of the following is the most likely
diagnosis?
A) Adenocarcinoma of the lung
B) Large cell lymphoma
C) Metastatic osteosarcoma
D) Metastatic renal cell carcinoma
E) Small cell carcinoma of the lung
F) Squamous cell carcinoma of the lung
Correct Answer: F.
Squamous cell carcinoma of the lung is the second most common type of primary
lung cancer after adenocarcinoma. Risk factors for all major types of lung cancer
include tobacco use, secondhand smoke, asbestos, or radon exposure, and a family
history of lu -
13
Exam Section 1: Item 13 of 50
Național Board of Medical Examiners®
NBME 25
, 4
NBME 25
Comprehensive Basic Science Self-Assessment
13. A 45-year-old woman has had progressive fatigue and mild shortness of breath
with exertion during the past 3 months. She thinks she had rheumatic fever at the
age of 10 years. A grade 2/6, rumbling, diastolic murmur is heard at the fifth left
intercostal
space in the midclavicular line. A lateral x-ray of the chest shows mild posterior
displacement of the esophagus. Which of the following cardiovascular structures is
most likely responsible for the esophageal displacement?
O A) Descending aorta
B) Left atrium
C) Left ventricle
D) Right atrium
E) Right ventricle
Correct Answer: B.
In the typical anatomic orientation, the left atrium is the most posterior part of the
heart and lies anterior to the esophagus in the mediastinum. In this patient, the left
atrium is most likely enlarged secondary to mitral -
14
Exam Section 1: Item 14 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
14. A 34-year-old woman is brought to the emergency department by her husband
because of an inability to see objects in the peripheral visual fields in both eyes for 1
day. Her temperature is 37.2°C (99°F), pulse is 68/min, respirations are 16/min, and
blood
pressure is 124/78 mm Hg. Automated computerized perimetry examination shows a
loss of the temporal visual field in both eyes. Neurologic examination shows no other
abnormalities. This patient is most likely to have which of the following additional
findings?
A) Amenorrhea
B) Aphasia
C) Double vision
D) Loss of memory
E) Seizures
Correct Answer: A.
This patient's bitemporal hemianopsia is most likely the result of optic chiasm
compression from a pituitary adenoma, which is often associated with amenorrhea in
women secondary to the overproduction of pro -
15
Exam Section 1: Item 15 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
15. A 46-year-old man with type 2 diabetes mellitus is brought to the emergency
department by his wife 30 minutes after he developed chest pain and then lost
NBME 25
