Answer:
c. Crossing over
Step-by-step explanation:
In meiosis, crossing over refers to the process where homologous chromosomes 'combine' with each other in order to exchange genetic material, which results in genetic variation. This process takes place during Prophase I of the first meiotic division.
Crossing over is extremely important for the variation - and survival - of a species, as it results in numerous genetic combinations that are passed from generation to generation.