57. In astronomy the term "red shift" denotes [U]the extent to which light from a distant galaxy has been shifted[/U] toward the red, or long-wave, end of the light spectrum by the rapid motion of the galaxy away from the Earth.
(A) to which light from a distant galaxy has been shifted
(B) to which light from a distant galaxy has shifted
(C) that light from a distant galaxy has been shifted
(D) of light from a distant galaxy shifting
(E) of the shift of light from a distant galaxy
Choice A is best because it is idiomatic and because its passive verb construction, has been shifted, clearly indicates that the light has been acted upon by the rapid motion. In B, the active verb has shifted suggests that the light, not the motion, is the agency of action, but such a construction leaves the phrase by the rapid motion of the galaxy away from the Earth without any logical or grammatical function. In C, the construction the extent that light is ungrammatical; denotes the extent must be completed by to which. D incorrectly employs an active verb, shifting, and extent of light is imprecise and awkward. E is faulty because it contains no verb to express the action performed by the rapid motion
