Human somatic (body) cells have chromosomes while human gametes (se) cells have chromosomes.

Human somatic (body) cells have 46 chromosomes while human gametes cells have 23 chromosomes.

Explanation:

The somatic cell of the human body are diploid in nature i.e. 2n hence 46 chromosomes and 23 pairs in them while the gametes cells are haploid in nature i.e n so half of 46 that is 23.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.