Which among the following is the outer layer of the blastocyst?

Trophoblast.

The correct answer is Option (3)- Trophoblast.

Explanation:

The blastocyst is an early stage in embryonic development, consisting of a hollow sphere of cells. It has an outer layer called the trophoblast and an inner cell mass.

The trophoblast is the outer layer of cells that surrounds the blastocyst. It plays a crucial role in implantation and the formation of structures necessary for the embryo to obtain nutrients and establish a connection with the maternal tissues. The inner cell mass gives rise to the embryo itself.

So, among the given options, the correct answer is Trophoblast.