question_answer

Jenny set up 2 tanks labeled A and B. She placed fishes in each tank but she put hydrilla (an aquatic plant) in tank A only. Jenny found that fishes swam freely in tank A but fishes in tank B swam near to the bottom water surface. Jenny concluded that hydrilla:

A) Help to beautify the aquarium.

B) Provide shade for the fishes.

C) Are the main source of food for the fishes.

D) Provide oxygen for the fishes to breathe during photosynthesis.

E) None of these