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
The major source of estrogen after menopause is? 
Select and explain. 
A. Aromatization of androgens in theca cells of ovary, B. Aromatization of androgens in granulosa cells of the ovary, C. Aromatization of androgens in adipose tissue, D. Adrenal production of estrogens
C: Aromatization of androgens in adipose tissue
Answer: C: Aromatization of androgens in adipose tissue 
Explanation: Androgen production from the ovary continues beyond menopausal transition caused by sparing of ovarian stroma and theca cells. However due to loss of granulosa cell function, ovary does not contribute to estrogen production by aromatization of androgens. The most impoant source of estrogen is peripheral conversion of androgens produced by ovary and adrenals, principally occurring in adipose tissue.