OG113解释的问题

113. Visitors to the park have often looked up into the leafy canopy and saw monkeys sleeping on the branches. whose arms and legs hang like socks on a clothesline.

(A)  saw monkeys sleeping on the branches, whose arms and legs hang

(B)   saw monkeys sleeping on the branches, whose arms and legs were hanging

(C)  saw monkeys sleeping on the branches, with arms and legs hanging

(D)  seen monkeys sleeping on the branches, with arms and legs hanging

(E)   seen monkeys sleeping on the branches, whose arms and legs have hung

Choice D, the best answer, not only forms a correct and clear sentence by supplying the present perfect verb have ... seen, but also solves the problem of the whose ... clause by using the appropriately placed adverbial phrase with arms and legs hanging... to modify sleeping.

为什么说with arms and legs hanging...是副词短语?我认为是介词短语作伴随情况状语啊.请指教.

没有人回答?顶一下.