"How Does the Foraging of Animals on Tree Seeds Affect

"How does the foraging of animals on tree seeds affect the distribution and abundance of the trees? " This question

A) would require an elaborate experimental design to answer.
B) is difficult to answer because a large experimental area would be required.
C) is difficult to answer because a long-term experiment would be required.
D) is a question that a present-day ecologist would be likely to ask.
E) A, B, C and D are correct.