Microevolution, or evolution at its smallest scale, occurs when
a) an individual's traits change in response to environmental factors.
b) a community of organisms changes due to the extinction of several dominant species.
c) a new species arises from an existing species.
d) a population's allele frequencies change over a span of generations.
e) none of the above.

D) a population's allele frequencies change over a span of generations.

Explanation:

Microevolution occurs within a population whereby gene flow, mutation, genetic drift or natural section brings about a change in a population’s allele frequencies over several generations. It occurs on a small scale. Examples of microevolution can be observed in resistance being evolved by pests to pesticides. i.e. Mosquitoes developing resistance against DDT. Mosquitoes with genes that can withstand DDT have evolved overtime.

an individual’s sex (i.e., whether they are a male or female) is determined by the sex chromosomes. most people have two sex chromosomes, one that is inherited from their mother and one that is inherited from their father. typically, females have two x chromosomes (xx) and males have one x chromosome and one y chromosome (xy). conditions caused by changes (“mutations”) in genes located on the x chromosome are considered x-linked.

x-linked recessive inheritance

most x-linked conditions are recessive. this means that in a person with two x chromosomes (most females), both copies of a gene (i.e., one on each x chromosome) must have a change or mutation whereas in a person with one x chromosome (most males), only one copy of a gene must have a mutation. a female with a mutation in one copy of a gene on the x chromosome is said to be a “carrier” for an x-linked condition. a male with a mutation in a gene on the x chromosome is typically affected with the condition. because females have two copies of the x chromosome and males have only one x chromosome, x-linked recessive diseases are more common among males than females. however, x-linked recessive diseases can occur in both males and females.

for x-linked recessive disorders, an unaffected carrier mother who has a mutation in a gene on the x chromosome can transmit either the x chromosome with this mutation or a “normal” x chromosome to her children. if the father is unaffected, none of her daughters will be affected and all of her daughters will be unaffected—since they will inherit at least one normal x chromosome from their father. however, each daughter will have a 50% chance of being an unaffected carrier like her mother and a 50% chance of both x chromosomes being normal.

your answer is going to be physical weathering