Use the Graph Below, Which Shows Changes During the Menstrual $\mathrm{E}$

Use the graph below, which shows changes during the menstrual cycle, to answer the following Questions

-The cause of the sudden increase shown at point $\mathrm{E}$ is

A) negative feedback of progesterone on the hypothalamus
B) negative feedback of estrogen on the anterior pituitary
C) negative feedback of follicle-stimulating hormone (FSH) on the ovary
D) positive feedback of FSH on the ovary
E) positive feedback of estrogen on the anterior pituitary