Development of the embryo begins at stage 1 when sperm fertilizes an oocyte and together they form a zygote. Human development begins after the union of male and female gametes or germ cells during a process known as fertilization (Conception).
Meiosis.
Meiosis results in four cells of the original, each with a halved amount of chromosomes, you could say.
Out of the factors listed, cold temperature decreases the rate of a chemical reaction within cells. This will make the correct answer D.
