Q17

Responding to the public’s fascination with-and sometimes

undue alarm over-possible threats from asteroids, a scale

developed by astronomers rates the likelihood that a particular

asteroid or comet may collide with Earth.

A.     a scale developed by astronomers rates the likelihood

that a particular asteroid or comet may

B.     a scale that astronomers have developed rates how

likely it is for a particular asteroid or comet to

C.     astronomers have developed a scale to rate how likely

a particular asteroid or comet will be to

D.     astronomers have developed a scale for rating the

likelihood that a particular asteroid or comet will

E.      astronomers have developed a scale that rates the

likelihood of a particular asteroid or comet that may.

the answe is C. But i do not hold that C should be the right answer for will and to do something is repetitive. My choice is D. COuld you offer your views?

I also chose D, the "to be " in choice C is awkward. don't know why C is right??