A haploid cell has how many sets of chromosomes?

A haploid cell contains one set of chromosomes. This means that there is a single complete set of genetic information, typically represented as "n". In organisms that reproduce sexually, haploid cells are important because they are involved in the formation of gametes—sperm and egg cells. When two haploid gametes fuse during fertilization, they form a diploid cell, which contains two sets of chromosomes (one from each parent).

Understanding the significance of haploid cells also highlights their role in maintaining genetic diversity through sexual reproduction. This is crucial for evolutionary processes. In contrast, other choices represent multiple sets of chromosomes, which are characteristic of diploid (two sets) or polyploid (three or more sets) organisms, and do not apply to haploid cells.