The changes that occur in females at the onset of puberty are:

For what primary purpose is the call of the cuckoo heard during the rainy season?

Match Column-$I$ with Column-$II$:

Column-$I$	Column-$II$
$(A)$ Mons pubis	$(1)$ Embryo formation
$(B)$ Antrum	$(2)$ Sperm
$(C)$ Trophectoderm	$(3)$ Female external genitalia
$(D)$ Nebenkern	$(4)$ Graafian follicle

Given below are two statements:
Statement $I$: Ovulation is caused by $LH$ surge leading to rupture of Graafian follicles.
Statement $II$: Graafian follicle remaining after ovulation transform into corpus luteum and secretes large amount of estrogen.
In the light of the above statements, choose the most appropriate answer from the options given below:

Which of the following statements are true about the female reproductive system?
$(A)$ Both estrogen and progesterone are necessary for development of follicle
$(B)$ Progesterone production is under the control of $LH$
$(C)$ The part of the oviduct is isthmus; has a narrow lumen and it joins the uterus
$(D)$ During pregnancy all events of the menstrual cycle stop and there is no menstruation
$(E)$ The graafian follicle ruptures to release the primary oocyte from the ovary by the process called ovulation

Ovulation takes place in/on