The process of evolution, or genetic change over time, has resulted in the wide variety of living things that exist today. In what ways do mutations play a part in the processes involved in the evolution of species?

a
Many mutations that occur will spread quickly throughout a population, creating new species.
b
Some mutations are contagious and lethal, which can lead to the extinction of a population.
c
If the mutation is beneficial, it will become more prevalent in the population's genes over time.
d
Any mutations that occurs may affect the population's gene pool that is already established.