You are presented with the quiz "Migration increases what?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "gene flow occurs when individuals move into or out of a population" and "internal migration describes moves within a country". So, what's the best answer to the question?

Choose your answer from:
- root growth
- speed
- distance
- voltage
- energy usage
- Plants growth
- gene flow
- layers of fat
Answer:
gene flow