Humans have developed different dog breeds using the process of selective breeding.
how is selective breeding similar to evolution by natural selection?
a. both are driven by the environment's goals.
b. both are driven by human goals.
c. both occur over several generations.
d. both select for favorable traits in a species.

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.