Question

which of the following contribute to a populations heritable genetic variation? choose 1 answer: a natural selection and sexual reproduction b sexual reproduction and mutations c mutations and acquired traits

Explanation:

• Option A: Natural selection acts on existing genetic variation (it doesn't create new heritable variation) and sexual reproduction shuffles existing genes but mutations are the primary source of new genetic material. So A is incorrect.
• Option B: Sexual reproduction (through processes like crossing - over and independent assortment) shuffles existing genetic material to create new combinations, and mutations introduce new genetic material (new alleles) into the population. Both contribute to heritable genetic variation.
• Option C: Acquired traits are not heritable (they are changes in an organism's phenotype due to the environment, not changes in the DNA), so they do not contribute to heritable genetic variation. So C is incorrect.

Answer:

B. sexual reproduction and mutations