How many non-autosomal genes does a human typically possess?

Humans typically possess one non-autosomal gene. This gene is located on the Y chromosome, which is one of the two sex chromosomes in humans (the other being the X chromosome). While most genes are located on the 22 pairs of autosomes, the genes located on the X and Y chromosomes are classified as non-autosomal.

In human males, who possess one X and one Y chromosome, the only non-autosomal gene is found on the Y chromosome. This gene has crucial functions related to sex determination and spermatogenesis. In females, who have two X chromosomes, there are no Y-linked genes present, which reinforces the understanding that typically only one non-autosomal gene exists in the context of the entire human genome.

The other potential answers misinterpret the number of non-autosomal genes. While zero suggests the absence of these genes, and options suggesting two or three would exceed the count related to non-autosomal genes in a typical human genome.