Data analysis

Answer Key Probabilities

How often each choice (A, B, C, D) was keyed as the correct answer across the biomedical engineering question bank — 1,315 unique MCQs analyzed.

Overall most likely
B (38.4%)
Least likely
D (13.6%)
Banks covered
6

All question banks combined

1,315 unique MCQs across the 697 bank, Gondar 2018, Hawassa & Gondar 2026, and JU by Yared.

Questions
1,315
Most likely
B
Choice A292 (22.2% · P=0.222)

95% CI: 20.0% – 24.4%

Choice BTop505 (38.4% · P=0.384)

95% CI: 35.8% – 41.0%

Choice C336 (25.6% · P=0.256)

95% CI: 23.2% – 27.9%

Choice D179 (13.6% · P=0.136)

95% CI: 11.8% – 15.5%

Uniform baseline: 25% eachχ² = 167.0 · skewedEntropy: 1.91 bits

How to use this

These probabilities reflect how often each letter was keyed as correct in past papers — not a rule for future exams. Choice B is the most common overall (38.4%), while D is least common (13.6%), especially in Gondar 2026 samples. Always eliminate wrong options first; use letter frequency only as a last resort when guessing.