NBME CBSE REAL EXAM-STYLE QUESTIONS
(USMLE STEP 1)LATEST UPDATE 2026
QUESTIONS WITH VERIFIED ANSWERS
Question 1
A 70-year-old man dies in a motor vehicle collision. He had
been undergoing evaluation for occult blood in the stool. A
photograph of the resected transverse colon shows a polyp
with a pedunculated growth pattern. Microscopy reveals
crowded, branched tubular glands with elongated,
hyperchromatic nuclei. What is the most likely diagnosis?
A) Hyperplastic polyp
B) Tubular adenoma
C) Villous adenoma
D) Adenocarcinoma
E) Peutz-Jeghers polyp
Correct Answer: B) Tubular adenoma
Rationale: This is a classic description of a tubular adenoma,
the most common type of colorectal polyp. The presence of
,crowded, branched tubular glands with hyperchromatic nuclei
is characteristic. It is a premalignant lesion, and the risk of
malignancy correlates with size, villous component, and degree
of dysplasia.
Question 2
A 38-year-old man presents with a one-week history of
watery, itchy eyes and a runny nose. Physical examination
shows inflamed nasal mucosa and clear rhinorrhea. There is no
congestion in the lower lungs. Which of the following is the
most appropriate pharmacotherapy?
A) Diphenhydramine
B) Loratadine
C) Montelukast
D) Prednisone
E) Oxymetazoline
Correct Answer: B) Loratadine
Rationale: The patient has symptoms of allergic rhinitis
without lower respiratory involvement. A second-generation,
non-sedating antihistamine like loratadine is appropriate first-
line therapy. Diphenhydramine (A) is a first-generation
antihistamine that causes sedation. Montelukast (C) is used
primarily for asthma and allergic rhinitis but is not first-line.
,Question 3
A 16-year-old girl presents with a 3-day history of fever,
nonproductive cough, and fatigue. Temperature is 38.3°C.
Chest x-ray shows bilateral interstitial infiltrates. Blood
drawn for culture spontaneously agglutinates while awaiting
transport to the laboratory. Cold agglutinins are positive.
Which antibody isotype is responsible for this agglutination?
A) IgA
B) IgD
C) IgE
D) IgG
E) IgM
Correct Answer: E) IgM
Rationale: This patient has Mycoplasma
pneumoniae pneumonia. The organism induces the production
of cold agglutinins, which are IgM antibodies that agglutinate
red blood cells at cold temperatures. IgM is a pentamer and a
potent agglutinin, making it responsible for this phenomenon.
Question 4
, A 24-year-old man presents with small, tender blisters on his
penis three days after unprotected sexual intercourse. A
photograph shows grouped vesicles on an erythematous base
on the glans penis. What is the most likely causal agent?
A) Treponema pallidum
B) Herpes simplex virus type 1
C) Herpes simplex virus type 2
D) Human papillomavirus
E) Haemophilus ducreyi
Correct Answer: C) Herpes simplex virus type 2
Rationale: The clinical presentation of grouped vesicles on an
erythematous base in the genital area three days after
unprotected sex is highly suggestive of genital herpes caused
by HSV-2. HSV-1 can cause genital herpes but is less common.
Question 5
A 42-year-old woman has a 3-year history of an intermittent
facial rash affecting the forehead, eyelids, nose, and cheeks.
The rash has worsened since she moved from New York to
Florida. She reports that spicy foods precipitate a flushing
reaction that exacerbates the rash. Physical examination
reveals erythema over the nose and cheeks, scattered
(USMLE STEP 1)LATEST UPDATE 2026
QUESTIONS WITH VERIFIED ANSWERS
Question 1
A 70-year-old man dies in a motor vehicle collision. He had
been undergoing evaluation for occult blood in the stool. A
photograph of the resected transverse colon shows a polyp
with a pedunculated growth pattern. Microscopy reveals
crowded, branched tubular glands with elongated,
hyperchromatic nuclei. What is the most likely diagnosis?
A) Hyperplastic polyp
B) Tubular adenoma
C) Villous adenoma
D) Adenocarcinoma
E) Peutz-Jeghers polyp
Correct Answer: B) Tubular adenoma
Rationale: This is a classic description of a tubular adenoma,
the most common type of colorectal polyp. The presence of
,crowded, branched tubular glands with hyperchromatic nuclei
is characteristic. It is a premalignant lesion, and the risk of
malignancy correlates with size, villous component, and degree
of dysplasia.
Question 2
A 38-year-old man presents with a one-week history of
watery, itchy eyes and a runny nose. Physical examination
shows inflamed nasal mucosa and clear rhinorrhea. There is no
congestion in the lower lungs. Which of the following is the
most appropriate pharmacotherapy?
A) Diphenhydramine
B) Loratadine
C) Montelukast
D) Prednisone
E) Oxymetazoline
Correct Answer: B) Loratadine
Rationale: The patient has symptoms of allergic rhinitis
without lower respiratory involvement. A second-generation,
non-sedating antihistamine like loratadine is appropriate first-
line therapy. Diphenhydramine (A) is a first-generation
antihistamine that causes sedation. Montelukast (C) is used
primarily for asthma and allergic rhinitis but is not first-line.
,Question 3
A 16-year-old girl presents with a 3-day history of fever,
nonproductive cough, and fatigue. Temperature is 38.3°C.
Chest x-ray shows bilateral interstitial infiltrates. Blood
drawn for culture spontaneously agglutinates while awaiting
transport to the laboratory. Cold agglutinins are positive.
Which antibody isotype is responsible for this agglutination?
A) IgA
B) IgD
C) IgE
D) IgG
E) IgM
Correct Answer: E) IgM
Rationale: This patient has Mycoplasma
pneumoniae pneumonia. The organism induces the production
of cold agglutinins, which are IgM antibodies that agglutinate
red blood cells at cold temperatures. IgM is a pentamer and a
potent agglutinin, making it responsible for this phenomenon.
Question 4
, A 24-year-old man presents with small, tender blisters on his
penis three days after unprotected sexual intercourse. A
photograph shows grouped vesicles on an erythematous base
on the glans penis. What is the most likely causal agent?
A) Treponema pallidum
B) Herpes simplex virus type 1
C) Herpes simplex virus type 2
D) Human papillomavirus
E) Haemophilus ducreyi
Correct Answer: C) Herpes simplex virus type 2
Rationale: The clinical presentation of grouped vesicles on an
erythematous base in the genital area three days after
unprotected sex is highly suggestive of genital herpes caused
by HSV-2. HSV-1 can cause genital herpes but is less common.
Question 5
A 42-year-old woman has a 3-year history of an intermittent
facial rash affecting the forehead, eyelids, nose, and cheeks.
The rash has worsened since she moved from New York to
Florida. She reports that spicy foods precipitate a flushing
reaction that exacerbates the rash. Physical examination
reveals erythema over the nose and cheeks, scattered
