Which chromosome combination typically produces males?

The typical chromosome combination that produces males is the XY chromosomes. In humans, biological sex is determined by the combination of sex chromosomes inherited from the parents. Males possess one X chromosome and one Y chromosome, while females have two X chromosomes.

The presence of the Y chromosome is crucial because it carries the SRY gene (Sex-determining Region Y gene), which initiates the development of male characteristics by triggering the formation of testes and the production of male hormones, such as testosterone. This hormonal influence leads to the development of male physical and reproductive traits.

In contrast, the other combinations listed do not correspond to the typical genetic makeup for males. For instance, YY chromosomes are not viable in humans; an X chromosome only would not provide the male-specific traits required; and ZY chromosomes are not a recognized sex-determination system in humans. Therefore, the XY chromosome combination is correctly identified as the one that typically results in male phenotype development.