Fusion of two gametes is called

The correct answer is A. Fertilization.

Fertilization is the fusion of two gametes, a male gamete (sperm) and a female gamete (ovum), to form a zygote. The zygote is the first cell of a new organism.

B. Development is the process by which an organism grows and changes from a single cell to a multicellular organism.

C. Regeneration is the process by which an organism can replace lost or damaged parts.

D. Pollination is the transfer of pollen from the male part of a flower to the female part of a flower.