Read the passage and answer the questions:
Implantation is the embedding of the blastocyst into the endometrium of the uterus. Blastocyst is a ball of cells with a large, fluid-filled cavity called the blastocoel. The blastomeres in the blastocyst are arranged into an outer layer called trophoblast and inner cell mass. With the formation of blastocoel, morula is converted to blastula which is called blastocyst in mammals.
The ectoderm cells will form the........

Options

A. Skeletal system
B. Nervous system
C. Excretory system
D. Respiratory system

Answer

B

Explanation

Ectodermal cells form the central nervous system.