<span> Geographical</span> isolation refers to a
population of organisms (such as plants and animals) that are separated
from other species, thus unable to exchange genetic material with other
organisms because of physical boundaries that isolate them or any
unfavorable circumstances that prevent interbreeding.
The answer is D. Zygote. A zygote is formed by the fertilization of an egg by a sperm. A gamete is what we refer to an egg or sperm as. Fertilization is what we call when a sperm and an egg come together, but it is not the product of the two.
