The pioneering research of Lewis Latimer and Thomas Edison, who became

Official Explanation

In the original sentence, the pronoun “his” lacks a clear antecedent, making it unclear whether it was “Lewis Latimer” or “Thomas Edison” who “became known for his invention of the light bulb.” In fact, the plural phrase "Lewis Latimer and Thomas Edison" leads us to expect a plural pronoun later on; if we only wish to refer to "Thomas Edison," we should position the modifying phrase so as to refer to "Thomas Edison" only.

Also, the construction “who became known for his invention” is wordy and could be replaced by the more concise form “known for his invention.”

(A) This choice is incorrect as it repeats the original sentence.

(B) This answer choice replaces the wordy construction “who became known for his invention” with the more concise form “known for his invention,” but retains the original ambiguity stemming from the lack of a clear antecedent for the pronoun “his.”

(C) CORRECT. By placing the modifier “known for his invention of the light bulb” immediately after “Thomas Edison” and prior to the introduction of “Lewis Latimer,” this answer choice resolves the original ambiguity and makes it clear that the pronoun “his” refers to “Thomas Edison” rather than “Lewis Latimer.” The construction “known for his invention” is also more concise than the original form “who became known for his invention.”

(D) This answer choice illogically states that it was the “pioneering research” rather than “Thomas Edison” that became “known for his invention of the light bulb,” thus altering the original meaning of the sentence. Further, this answer choice retains the original problem of ambiguity by failing to provide a clear antecedent for the pronoun “his.”

(E) This answer choice uses the passive construction “research that was conducted by Thomas Edison” rather than the more direct and concise form “research of Thomas Edison.” Further, while the placement of the modifier “who became known for his invention of the light bulb” next to Thomas Edison and prior to the introduction of “Lewis Latimer” resolves the ambiguity, the phrase “who became known for his invention” is wordy; the more concise form “known for his invention” is preferable.

Answer: C