Which individuals should avoid vitamin c supplements because of above-normal risk of negative effects? ?

Excess of everything is bad. This rule also applies to the level of vitamins in our body. For example, the high level of Vitamin C in body is not good and can result in some adverse effect.  

Vitamin C is a water soluble vitamin which means it doesn’t stay in body and excrete with water.

People who take supplements with high level of vitamin C can face digestive distress and kidney stones. It is because the excess level of vitamin C starts accumulating in body. Excess vitamin C in body can cause diarrhea and nausea and also kidney stones.

So people who have kidney stones and such related conditions should not take vitamin C.

organisms that lack symmetry are called asymmetrical and belong to phylum porifera/sponges.

organisms with specialized stinging cells belong to phylum cnidaria. stinging cells are called cnidoblast cells.

cnidarians show two morphological forms : polyp (sessile) and medusa (mobile)

filter feeding is observed in porifera members.  

alternation of generation is observed in coelenterata or cnidaria. there is alternation of asexual polyp form and sexual medusoid form. it is also referred as metagenesis.

the answer is c.mitochondria. glad to .