This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Normal Menstruation, Abnormal Menstruation, Menopausal Physiology and forsight of conception, Subject name: Gynaecology & Obstetrics
Stimulation of ovary in the early follicular phase is by: 
Select and explain. 
A. Oestrogen, B. Progesterone, C. FSH, D. LH
C: FSH
Answer: C: FSH 
Explanation: Stimulation of ovary in early follicular phase is by FSH, as the growth and differentiation of primordial follicles are under the control of FSH. Presence of FSH prevents follicles from undergoing Atresia. Stimuation of ovary in later follicular phase is predominantly by FSH but also LH is required in later follicular stage for the final maturity of the follicle before rupture.