The type of placenta found in human beings is of type

Which cavity arises by the invagination of endoderm and mesoderm?

Thalidomide is a non-barbiturate sedative drug which was given to pregnant women. Its use was withdrawn in $1961$ because it resulted in phocomelia. This condition illustrates:

Identify $A$ to $D$ in the given figure.

$A$ post-gastrula embryo contains:

Which of the following germ layers gives rise to the germ cells?