This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Physiology & Histology, Subject name: Gynaecology & Obstetrics
A sample of cervical mucus is taken on Day 12 of the menstrual cycle: The mucus is thin, clear, elastic. It is placed on a slide and allowed to air dry. When placed under microscope, what would you expect: 
Select and explain. 
A. Clear field devoid of bacteria, B. Thick mucus with back ground bacteria, C. A fern pattern characteristic of estrogen, D. Clearly defined, parabasal cells
C: A fern pattern characteristic of estrogen
Answer: C: A fern pattern characteristic of estrogen 
Explanation: Ans. is c, i.e. A fern pattern characteristic of estrogen.On day 12, when cervical mucus is viewed under microscope, it shows a fern like pattern under the effect of estrogen.