The repressor theory of activation of fertilization was proposed by:

Where does fertilization occur in mammals?

Where are the Columnar cells found?

What triggers the acrosome reaction in a sperm?

$A$: Fertilizins are glycoproteins present on the surface of the egg membrane.
$R$: They help in the agglutination reaction by interacting with anti-fertilizins on the sperm surface to facilitate fertilization.

Identify the human developmental stage shown below as well as the related right place of its occurrence in a normal pregnant woman,and select the right option for the two,together.