A. The small fish and wading birds would be affected.
B. Only the small fish would be affected.
C. The small fish, bivalves, and invertebrates would be affected
D. The entire food web would be affected.

well for one plants are always the producer, so a is the answer. a wolf is more of the consumer(predator) and the deer is the prey so i know those two are out of the question. also mushrooms are fungi/fungus so a is the producer.