b. an excretory system that includes a pair of kidneys.
c. a system of muscles that enable movement.
d. all of the above
Answer:
If a geneticist is studying the visible expression of allele combinations in an organism, such as its height, hair color, and eye color, they are studying the organism's phenotype. Therefore, the correct answer is b) Phenotype.
Answer:Ninjbhwhi
Explanation: