Evolution means
a. that populations of organisms change over time.
b. organisms are constantly created by a deity.
c. species are unrelated in the earth's environment.
d. an organism changes in its lifetime.

Evolution means that populations of organisms change over time.

Explanation:

Evolution refers to the phenomena by which a population develops new traits and becomes more and more fit to survive in a given environment.

Evolution can be studied in two different ways- as a pattern of evolutionary changes and as a process of evolution.

Study of Evolution help us to understand the history of life.

Evidences of evolution support the view that species evolved from common ancestors rather than created separately..

These evidences are contributions of various fields of biology and geology.

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.