COMSAE Phase 2 – BSA 119 Questions With
Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. A 67-year-old man presents with sudden-onset chest pain
radiating to the left arm. ECG shows ST elevation in leads II, III, and
aVF. Which coronary artery is most likely occluded?
A. Left anterior descending artery
B. Left circumflex artery
C. Right coronary artery
D. Posterior descending artery
Answer: C. Right coronary artery
Rationale: Inferior wall myocardial infarction is classically
associated with ST elevation in leads II, III, and aVF. The right
coronary artery most commonly supplies the inferior wall of the
heart.
2. A newborn fails the meconium passage within 48 hours and has
abdominal distension. Rectal biopsy shows absence of ganglion
, cells. What is the diagnosis?
A. Cystic fibrosis
B. Hirschsprung disease
C. Pyloric stenosis
D. Intussusception
Answer: B. Hirschsprung disease
Rationale: Hirschsprung disease is due to failure of neural crest
cell migration, resulting in absence of ganglion cells in the distal
colon and functional obstruction.
3. A patient with COPD is given oxygen therapy. Which complication
is most concerning with high-flow oxygen?
A. Respiratory alkalosis
B. Oxygen toxicity
C. CO₂ retention
D. Metabolic acidosis
Answer: C. CO₂ retention
Rationale: COPD patients rely on hypoxic drive for respiration;
high oxygen can reduce ventilatory drive and worsen CO₂
retention.
,4. A 25-year-old woman presents with exophthalmos, heat
intolerance, and weight loss. Labs show low TSH and high T4.
What is the mechanism?
A. Thyroid adenoma secreting TSH
B. Autoantibodies stimulating TSH receptors
C. Pituitary adenoma secreting TSH
D. Thyroid hormone resistance
Answer: B. Autoantibodies stimulating TSH receptors
Rationale: Graves disease is caused by thyroid-stimulating
immunoglobulins that activate TSH receptors, increasing thyroid
hormone production.
5. A child presents with a “slapped cheek” rash. What is the
causative agent?
A. Rubella virus
B. Parvovirus B19
C. Measles virus
D. Coxsackievirus
Answer: B. Parvovirus B19
Rationale: Erythema infectiosum (“fifth disease”) is caused by
parvovirus B19.
, 6. A patient has tremor at rest, bradykinesia, and rigidity. Which
brain structure is primarily affected?
A. Cerebellum
B. Substantia nigra
C. Hippocampus
D. Caudate nucleus
Answer: B. Substantia nigra
Rationale: Parkinson disease results from degeneration of
dopaminergic neurons in the substantia nigra pars compacta.
7. A woman presents with dysuria and frequent urination. Urinalysis
shows nitrites and leukocyte esterase. Most likely organism?
A. Staphylococcus saprophyticus
B. Escherichia coli
C. Proteus mirabilis
D. Klebsiella pneumoniae
Answer: B. Escherichia coli
Rationale: E. coli is the most common cause of uncomplicated
urinary tract infections and produces nitrites from nitrate
reduction.
Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. A 67-year-old man presents with sudden-onset chest pain
radiating to the left arm. ECG shows ST elevation in leads II, III, and
aVF. Which coronary artery is most likely occluded?
A. Left anterior descending artery
B. Left circumflex artery
C. Right coronary artery
D. Posterior descending artery
Answer: C. Right coronary artery
Rationale: Inferior wall myocardial infarction is classically
associated with ST elevation in leads II, III, and aVF. The right
coronary artery most commonly supplies the inferior wall of the
heart.
2. A newborn fails the meconium passage within 48 hours and has
abdominal distension. Rectal biopsy shows absence of ganglion
, cells. What is the diagnosis?
A. Cystic fibrosis
B. Hirschsprung disease
C. Pyloric stenosis
D. Intussusception
Answer: B. Hirschsprung disease
Rationale: Hirschsprung disease is due to failure of neural crest
cell migration, resulting in absence of ganglion cells in the distal
colon and functional obstruction.
3. A patient with COPD is given oxygen therapy. Which complication
is most concerning with high-flow oxygen?
A. Respiratory alkalosis
B. Oxygen toxicity
C. CO₂ retention
D. Metabolic acidosis
Answer: C. CO₂ retention
Rationale: COPD patients rely on hypoxic drive for respiration;
high oxygen can reduce ventilatory drive and worsen CO₂
retention.
,4. A 25-year-old woman presents with exophthalmos, heat
intolerance, and weight loss. Labs show low TSH and high T4.
What is the mechanism?
A. Thyroid adenoma secreting TSH
B. Autoantibodies stimulating TSH receptors
C. Pituitary adenoma secreting TSH
D. Thyroid hormone resistance
Answer: B. Autoantibodies stimulating TSH receptors
Rationale: Graves disease is caused by thyroid-stimulating
immunoglobulins that activate TSH receptors, increasing thyroid
hormone production.
5. A child presents with a “slapped cheek” rash. What is the
causative agent?
A. Rubella virus
B. Parvovirus B19
C. Measles virus
D. Coxsackievirus
Answer: B. Parvovirus B19
Rationale: Erythema infectiosum (“fifth disease”) is caused by
parvovirus B19.
, 6. A patient has tremor at rest, bradykinesia, and rigidity. Which
brain structure is primarily affected?
A. Cerebellum
B. Substantia nigra
C. Hippocampus
D. Caudate nucleus
Answer: B. Substantia nigra
Rationale: Parkinson disease results from degeneration of
dopaminergic neurons in the substantia nigra pars compacta.
7. A woman presents with dysuria and frequent urination. Urinalysis
shows nitrites and leukocyte esterase. Most likely organism?
A. Staphylococcus saprophyticus
B. Escherichia coli
C. Proteus mirabilis
D. Klebsiella pneumoniae
Answer: B. Escherichia coli
Rationale: E. coli is the most common cause of uncomplicated
urinary tract infections and produces nitrites from nitrate
reduction.
