The Reason That Mutation at the Allele Level Can Lead

The reason that mutation at the allele level can lead to natural selection for whole organisms is that

A) mutation is always a beneficial process by which a species becomes better adapted to its environment with each passing generation.
B) altering even one allele changes the entire phenotype of an organism.
C) mutations occur early in development,during meiosis,when the genetic blueprint for all of an organism's cells is being determined.
D) genes provide the blueprints for anatomical or physiological structures that can influence the fitness of an organism in its environment.