Two offspring developed in the same uterus but from the fertilization of two different ova are:

Select the odd one out regarding the cells/layers associated with early embryonic development.

Given below are two statements.
Statement $I$: Mule is an intergeneric sterile hybrid.
Statement $II$: Mule is sterile due to failure of proper gametogenesis.
In the light of the above statements,choose the most appropriate answer from the options given below.

Which one of the following is the effect of higher $pH$ on the sperms?

Match the following columns and select the correct option.

Column-$I$	Column-$II$
$(a)$ Placenta	$(i)$ Androgens
$(b)$ Zona pellucida	$(ii)$ Human Chorionic Gonadotropin $(hCG)$
$(c)$ Bulbo-urethral glands	$(iii)$ Layer of the ovum
$(d)$ Leydig cells	$(iv)$ Lubrication of the Penis

Some important events in the human female reproductive cycle are given below. Arrange the events in a proper sequence. $A \rightarrow$ secretion of $FSH$,$B \rightarrow$ growth of corpus luteum,$C \rightarrow$ growth of the follicle and oogenesis,$D \rightarrow$ ovulation,$E \rightarrow$ sudden increase in the level of $LH$.