Why would the y chromosome be unlikely to contain any of the genes that are absolutely necessary for survival?

The Y chromosome

Explanation:

The Y chromosome is one of the two sex chromosomes in humans (the other is the X chromosome)The sex chromosomes form one of the 23 pairs of human chromosomes in each cellThe Y chromosome spans more than 59 million building blocks of DNA (base pairs) and represents almost 2 percent of the total DNA in cellsEach person normally has one pair of sex chromosomes in each cellThe Y chromosome is present in males, who have one X and one Y chromosome, while females have two X chromosomeThe Y chromosome is much smaller than the X chromosome and likely contains 50 to 60 genes that provide instructions for making proteinsOnly males have the Y chromosome, the genes on this chromosome tend to be involved in male sex determination and development hence unlikely to contain any of the genes that are absolutely necessary for survival Sex is determined by the SRY gene, which is responsible for the development of a fetus into a male

Since we don't see a strand; i got answers off a sheet and the correct answer is "2".