Which chromosomal pair determines the sex of an individual? Select one: a. 23rd b. 22nd c. 20th d. 19th

The correct answer is a. 23rd.<br /><br />The 23rd pair of chromosomes, also known as the sex chromosomes, determines the sex of an individual. In humans, there are two types of sex chromosomes: X and Y. Females typically have two X chromosomes (XX), while males have one X and one Y chromosome (XY). The presence of the Y chromosome determines male sex determination, while the absence of the Y chromosome results in female sex determination.