Answer:
D. reproduction
Explanation:
If the species doesn't reproduce they die out or become extinct.
The answer is (b.) fertilization
The fertilization is the stage where the egg cell or the
so-called ovum fused with the sperm cell which eventually leads the development
of the embryo or the zygote. The Embryogenesis starts when the zygote undergoes
mitotic divisions or also known cleavage process.
Salutations!
A group of cells working together are called tissues. Organisms are made up of this structure. Cells are the smallest unit of life. A group of tissues working together is called organ. A group of organs working together is called organ system. An organ system working together makes up an organism.
Hope I helped (:
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