What happens during development when only certain genes are expressed in
certain cells?
A. The cells have become mutated, so if the organism lives, it cannot
function normally.
B. The cells differentiate into types of tissues and organs specialized
for their functions.
C. The cells can only perform certain functions and only pass the
genes for those functions to their daughter cells.
D. The cells cannot perform all of the functions necessary for life,
and they die.