请教GMATprep的一道长SC

woaiwangwei

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

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

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

正确答案是E，这道题大家能不能为我指出B错在哪里

woaiwangwei

有没有人可以帮下忙

woaiwangwei

谢谢，斑竹大人热心的

woaiwangwei

错误1可不可以理解成researche have determined是插入语

?

woaiwangwei

恩，谢谢2位，我明白了。