a
The genes of most surviving parents have only dominant alleles.
b
Only recessive genes can be acted on by natural selection.
c
Parents with recessive genes die from overproduction.
d
Only traits that are controlled by genes can be acted on by natural selection.
d. Only traits that are controlled by genes can be acted on by natural selection. Genes play a crucial role in evolution as they are the units of heredity that are passed down from generation to generation. Natural selection acts on the variation in genes within a population, determining which traits are advantageous and therefore more likely to be passed on to future generations. This process leads to the evolution of populations over time.
