Which of these correctly distinguishes mitosis from meiosis?
a)mitosis occurs in germ cells and meiosis occurs in somatic cells.
b)crossing over takes place in mitosis and not in meiotic cell division.
c)meiosis produces four 2n daughter cells; mitosis produces two 2n daughter cells.
d)the number of chromosomes remains the same in mitosis and is reduced by half in meiosis.

Meiosis is the cell division needed to reproduce sexually, it produces the egg and sperm cells, which need to have half the amount of chromosomes, so that when they combine, they have the usual 46 chromosomes. All the other division, which produces identical cells of 46 chromosomes is called mitosis.

So the correct answer is:

D)The number of chromosomes remains the same in mitosis and is reduced by half in meiosis.