C. Mutations are a change in DNA or a chromosome and can be helpful, harmful or may have no affect.
Explanation:
Mutations are spontaneous random changes that occurs in the genetic make up of an organisms. Mutations are rare and their rate of occurrence is random.
Mutations may occur on the gene level known as gene mutations or at chromosome levels called chromosomal mutations.
Mutations may be beneficial, harmful or have no effect on a given organisms. Harmful mutations cause disorders that may lead to abnormality or death of an organisms. Beneficial mutations improve an organisms adaptability to the environment.
