Question

the yolk of an amniotic egg provides: external protection food supply for the embryo body temperature regulation oxygen exchange

Explanation:

The yolk of an amniotic egg is rich in nutrients. In the context of embryonic development within the egg, its main function is to serve as a food supply. External protection is mainly provided by the eggshell. Body temperature regulation is not a function of the yolk. Oxygen exchange occurs through structures like the eggshell pores and the chorio - allantoic membrane, not the yolk.

Answer:

Food supply for the embryo