Answer:
A
Explanation:
According to this hypothesis that pillar coral digested zooxanthellae, the coral digested zooxanthellae inside the pillar coral must be dead. If anything is engulfed then it should be first dead inside the body of the predator and then the energy is extracted from the food. The food eaten serves as a source of energy.
When two parents are purebred it means that they are homozygous for the characteristic that's being tested (in this case the fur colour). When they are crossed, the offspring will obligatory be heterozygous, an allele of each type from its parents. So, the trait that comes up will be the dominant trait, while the recessive trait will be hidden.