OG12 SC 73

Combining enormous physical strength with higher intelligence, the Neanderthals appear as equipped for facing any obstacle the environment could put in their path, but their relatively sudden disappearance during the Paleolithic era indicates that an inability to adapt to some environmental change led to their extinction.
A appear as equipped for facing any obstacle the environment could put in their path,
B appear to have been equipped to face any obstacle the environment could put in their path,
C appear as equipped to face any obstacle the environment could put in their paths,
D appeared as equipped to face any obstacle the environment could put in their paths,
E appeared to have been equipped for facing any obstacle the environment could put in their path,
请教各位大牛，我能排除 DEA 只是不明白equipped为何要用完成时态啊？？

我对OG解释的理解：
Neanderthals的disappearance是发生在过去的。
equip是发生在disappeared之前的动作。
如果用as equiped，是一般时（present tense），并不能表达这个动作“曾经发生”这个意思。
因此应该改用完成时。


同时，考虑到 in their path指的是这个人种在进化史上的发展道路，
所以应该是单数in their path，而不是in their paths，
所以CD也能排除