Ans.
Humans are diploid organisms that have 23 pairs of chromosomes (or 46 chromosomes) in all somatic or body cells. These cells divide by mitosis that forms daughter cells with same number of chromosome pairs as present in parent cell.
In humans, gametes (eggs and sperms) are formed from the germ cells by the process of meiosis that leads to reduction of chromosomes in daughter cells (with half the number of chromosomes as present in parent cell).
Thus, the correct options are:
-bone cell has 46 chromosomes, as bone is a somatic cell.
-skin cell has 23 chromosome pairs (46 chromosomes), as skin cell is somatic cell.
-gamete has half the chromosomes (23 chromosomes) of a red blood cell (46 chromosomes) as red blood cell is somatic cell.