Which conditions are necessary for natural selection? Check all that apply. Populations do not have genetic variation.
Populations have genetic variation.
The environment changes.
The environment stays the same.
Organisms must have specific traits in order to survive and reproduce.
Organisms with any traits will survive and reproduce.

Populations have genetic variation.

The environment changes.

Organisms must have specific traits in order to survive and reproduce.

Explanation:

Natural selection provides an advantage during an adverse condition for organisms that have a rich genetic variation in their population.

Also, environmental changes induced natural selection whereby organisms must adapt to changes around them.

For organisms to survive, they must have specific traits that gives them a competitive reproductive advantage.

first one is the correct answer

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.