Answer: The correct answer is -
B. Larva.
Step-by-step explanation:
Larva can be described as a particular stage during the development of many animals, which occurs after hatching and before the adult stage is reached. It is formed after egg and it is an immature, active form that is different in structure from that of adults. This stage is adapted is also adapted to varying environments.
Example - Insects undergo metamorphosis through stage of egg, which is followed by larva, pupa and finally adults.
Thus, zygote (that is fertilized egg) differentiates into larva after fertilization of egg (fusion of male and female gamete).