Question

practice it
union of sperm and ovum
lactation
gastrulation
fertilization
pollination
ovulation

Explanation:

Fertilization is the process where a sperm cell fuses with an ovum (egg cell). Lactation is milk - production in mammals. Gastrulation is a stage in embryonic development after fertilization. Pollination is related to plants and the transfer of pollen. Ovulation is the release of an egg from the ovary.

Answer:

C. fertilization