一题请指教。。。

45.
Hydrocarbons, with which fruit flies perfume themselves in species-specific
blends, are known to be important in courtship, and apparently this assists
flies that taste the hydrocarbons on prospective mates to distinguish their own
species from that of others.

A. and
apparently this assists flies that taste the hydrocarbons on prospective mates
to distinguish their own species from that of

B. and
apparently this assists flies when they taste the hydrocarbons on prospective
mates in distinguishing their own species from those of

C. which
apparently assists flies that tastes the hydrocarbons on prospective mates in
being able to distinguish their own species from

D. apparently
assisting flies to taste the hydrocarbons on prospective mates to distinguish
their own species from those of

E. apparently
assisting flies that taste the hydrocarbons on prospective mates in
distinguishing their own species from

D. apparently assisting flies to taste the hydrocarbons on prospective mates to distinguish their own species from those of others.

E. apparently assisting flies that taste the hydrocarbons on prospective mates in distinguishing their own species from others.

1） assit sb. to do 和 assit that 都对。

2） distinguish A from B . A 和 B 要对应。 D 中的 those 没有对应对象。