Hydrosphere and atmosphere. those are the only 2 spheres that interact with each other in the air.
Their change in position is caused by the movements of the tectonic plates.
Answer:
Mutations, gene flow, and sexual reproduction are all major causes of variation. By altering the genes of individuals in a population, DNA mutation causes genetic variation. As new individuals with different gene combinations migrate into a population, they cause genetic variation.
Explanation:
B)
The crust and the upper mantle.
