This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
Ovulation can be diagnosed by all except 
Select and explain. 
A. Measuring day 14 serum progesterone, B. Rise in basal body temperature in the second half of cycle, C. Study of cervical mucus, D. Endometrial histology
A: Measuring day 14 serum progesterone
Answer: A: Measuring day 14 serum progesterone 
Explanation: Tests for ovulation: Basal body temperature, Endometrial biopsy, Fern test, and ultrasound.
But plasma concentration of progesterone rises only after ovulation and reaches its the peak of 15ng/ml by mid-luteal phase.