The correct response is:
Mutations in somatic cells are not transmitted to gametes, which are necessary for reproduction.
Somatic cells are any cells in the body that are not gametes (sperm or egg cells). Mutations that occur in somatic cells will not be passed to the next generation because they do not affect the genetic material that is inherited by offspring. Only mutations that occur in the germline (the cells that give rise to gametes) can be passed on to future generations.