Answer: B. Two different sperm both fertilizing the same egg.
Explanation:
Fertilization is a process which involves the fusion of haploid gametes such as a sperm from male and an egg from female to develop a diploid zygote either inside the body of female mate (internal fertilization) or outside the body of female mate (external fertilization).
B. Two different sperm both fertilization the same egg. is the correct option. As only one sperm can fertilize the egg. The sperm brings changes in the external membrane of the egg which prevents the fusion with other sperm.
There is a very unique form of process for the as whole production of the different organisms inside the environment, as there are plant and animal species of which ancestors had a haploid (or half the number of chromosomes as compared to there parents) but they have a diploid form of chromosomes. Which would be certainly possible after the evolution which took place inside there genome and made them able to survive through generation having much similarity to there predecessors and that is how the species survived even though the process of alternation of generation( as explained) happened inside them.