Primary sex characteristics are

A) body parts directly related to reproduction.
B) pubic, facial, axillary, and body hair.
C) frequently the cause of pimples, blackheads, and acne.
D) the cause of the voice change.

Reproduction

Reproduction is the biological process by which new individual organisms are produced from their parents, essential for the survival of species.

Primary Sex Characteristics

The physical characteristics directly involved in reproduction, developing during puberty, including the ovaries in females, and the testes in males.

Body Parts

The distinct pieces or structures that make up the human or animal body.