Answer:
1. D (In population genetics, gene flow is the transfer of genetic material from one population to another.)
2. C (Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation. It can also cause initially rare alleles to become much more frequent and even fixed. When there are few copies of an allele, the effect of genetic drift is larger, and when there are many copies the effect is smaller.).
3. A and also E (Individuals with inherited characteristics that allow them to best compete for limited resources will survive and have more offspring than those individuals with variations that are less able to compete. Because characteristics are inherited, these traits will be better represented in the next generation.)
4. D (Gene flow can increase fitness but if it happens in another environment, it decreases the adaptability. If alleles are advantageous, the offsprings' inheritance increases.
5. B (Mutations are the main source of alleles)
