Angiosperms Are Unique in Having Double Fertilization That Forms Endosperm

Angiosperms are unique in having double fertilization that forms endosperm.What is true about double fertilization in angiosperms?

A) One pollen grain combines with the egg to form the zygote,and one pollen grain combines with the polar nuclei to form endosperm.Two sperm combine with a polar nucleus to form endosperm.
B) Two pollen grains combine with two ovules to form the zygote and endosperm.
C) One sperm combines with the polar nuclei to form the zygote,and one sperm combines with the egg to form endosperm.
D) One sperm combines with the egg to form the zygote,and one sperm combines with the polar nuclei to form endosperm.