I would say C because A is a positive, B is a positive, and D is a positive, The only "disadvantage" is in C
Producers are very important to ecosystem reason being without the producers we would not be able to survive. Producers make their own food by use of sun which turns simple raw materials into food.
Herbivores are consumers who eat only green plants. Omnivores eat animals and plants. Scavengers only eat dead organisms. Scavengers help the environment in that they eat dead organisms and decomposes the broken organic material down to the raw material.
The nasty fine ash is the smallest of the particles produced in a volcanic eruption. It can kill you if you breathe it in:)
