In the egg of a bird,the shell and shell membranes are:

Adolescence is a bridge linking .......... and .......... .
$(i)$ Adolescence $(ii)$ Childhood $(iii)$ Old age $(iv)$ Adulthood

Consider the following:
$A.$ The reductive division for the human female gametogenesis starts earlier than that of the male gametogenesis.
$B.$ The gap between the first meiotic division and the second meiotic division is much shorter for males compared to females.
$C.$ The first polar body is associated with the formation of the primary oocyte.
$D.$ Luteinizing Hormone $(LH)$ surge leads to disintegration of the endometrium and onset of menstrual bleeding.
Choose the correct answer from the options given below:

Which of the following pairs of homologous organs is incorrect?

The eggs of an elephant are:

Release of spermatozoa from the urethra by male animals is called: