Answer:
The correct answer are options a, b and d.
Step-by-step explanation:
The diversity of the types of cells and the functions in humans in comparison to simple animals can be accounted for various reasons. Some of them are as follows:
a. The genes in eukaryotes like in humans encode for various multiple proteins.
b. Differential gene expression results in complexity.
c. Complexity also originates due to the distinct combination of proteins.