Answer:
The healthies and strongest survive and reproduce
Explanation:
(A) a major change in an abiotic factor
Answer:
Cell differentiation is how cells become specialized. This occurs through a process called gene expression. Gene expression is the specific combination of genes that are turned on or off (expressed or repressed), and this is what dictates how a cell functions.
A) a common ancestor
Homologous structures are structures that are similar in related organisms. There is a basic pattern of bones which can be inherited from a common ancestor