Genetic variation can be introduced into a population by: a) mutation in an individual's genetic code
b) the bottleneck effect
c) the selection of the fittest individuals in the population
d) a new allele arising from a single mutation in a gene.

A

Explanation:

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both male and female gametes are produced by meiosis of the germ cells. therefore, both male and female gametes are haploid. one male and one female gamete unite during the fertilization to form the diploid zygote. in seed bearing plants, pollen grain is the male gametophyte, which produces sperm cells.