Pick from: (A). agriculture; (B). it needs them; (C). keeps the organism warm; (D). people worldwide; (E). our planet; (F). monkeys in trees; (G). tigers in the wild; (H). wolves in nature;
Given those answer options, answer the question: You are presented with the quiz "important food for waterfowl supply most of the food consumed by what?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "grasses supply most of the food consumed by people worldwide" and "grasses are also important food for waterfowl". So, what's the best answer to the question?
A:
(D).