It is unclear whether chimpanzees are unique among nonhuman

It is unclear whether chimpanzees are unique among nonhuman species in their ability to learn behaviors from one another, or if, when other animals are studied in as much depth, similar patterns would be found.

(A) if, when other animals are studied in as much depth, similar patterns would be found
(B) if other animals were studied with as much depth they would exhibit similar patterns
(C) would similar patterns be found in other animals if they were studied in as much depth
(D) whether similar patterns would be exhibited in other animals that were studied with as much depth
(E) whether other animals would exhibit similar patterns if they were studied in as much depth

Friends, noun reference also is a nightmare for me! To what do you say "they" in E refer? "patterns" or "animals"? Thanks!