During the development of an embryo, cells usually undergo a certain process. In this process, cells are fixed in development and become specialized to perform specific functions. What is this process called?

Cell differentiation.

Explanation:

This is because cell differentiation refer to the process where cell changes from one cell types to tissues or organs or even system or specialised cells during a developmental stages to perform functions. It occur in multicellular organisms where zygote changes to tissues or system.

. This occurs through a process called gene expression. Gene expression refer to the combination of genes that can either be expressed or repressed.

b.

a. to encourage apoptosis