Pandas!

[gmat_perfect]

Due to poaching and increased cultivation in their native habitats, researchers have determined that there are fewer than 100 Arabian leopards left in the wild, and that these leopards are thus many times as rare as China's giant pandas.

(A) Due to poaching and increased cultivation in their native habitats, researchers have determined that there are fewer than 100 Arabian leopards left in the wild, and that these leopards are thus many times as rare as
(B) Due to poaching and increased cultivation in their native habitats, there are fewer than 100 Arabian leopards left in the wild, researchers have determined, making them many times more rare than
(C) There are fewer than 100 Arabian leopards left in the wild due to poaching and increased cultivation in their native habitats, researchers have determined, which makes the leopards many times more rare compared to
(D) Researchers have determined that, because of being poached and increased cultivation in their native habitats, there are fewer than 100 Arabian leopards left in the wild, thus making them many more times as rare as
(E) Researchers have determined that, because of poaching and increased cultivation in their native habitats, there are fewer than 100 Arabian leopards left in the wild, and that these leopards are thus many times more rare than

[spoiler]OA: E[/spoiler]

[kvcpk]

"poaching and increased cultivation in their native habitats" did not cause researchers to determine something.
A is out

"making them many times more rare than " -> "them" is not clearly referring to its antecedent.
B is out.

"researchers have determined" is used as a non-essential modifier which is infact an essential information.
C is out.

"because of being poached and increased cultivation " not parallel. Moreover being poached is awkward.
D is out.

pick E.

[crackerman]

E.