Chromosome pairs that are composed of the X and Y chromosomes are called the

A) sex chromosomes.
B) gender chromosomes.
C) emotionality chromosomes.
D) autosomes.

Chromosome pairs that include the X and Y chromosomes are commonly known as sex chromosomes because they determine an individual's biological sex (male or female). The other options - gender chromosomes and emotionality chromosomes - are not scientifically recognized terms. Autosomes, on the other hand, refer to pairs of chromosomes that do not determine an individual's sex.