1)i know that chromosomes differ in shape, size and position of centromere but do chromosomes differ in gene composition? 2)does y chromosome has less genes than x hromosom?

i would go with b

cytokinesis occurs after telophase so that eliminates d

and the entire reason for cytokinesis is for cellular reproduction

the diploid number of chromosomes is sometimes represented by the symbol 2n. for the fruit fly, the diploid number is 8, which can be written as 2n = 8, where n represents twice the number of chromosomes in a sperm or egg cell.

i don't know. if i were you, i would search it up online : d