_______ new theory challenged decades of scientific consensus.

3
reading

Which choice completes the text so that it conforms to the conventions of Standard English?

A

Dr. Williams's

B

Dr. Williams'

C

Dr. Williams

D

Dr. Williamss'

Correct Answer: A

Choice A is the best answer. This question tests apostrophe usage with singular nouns ending in "s."

  1. Context clues: One person (Dr. Williams) possesses the theory.
  2. Meaning: For singular proper nouns ending in "s," add 's (modern standard).
  3. Verify: "Dr. Williams's new theory" follows the standard rule for singular possessives.

💡 Strategy: Singular nouns ending in "s" take 's for possession (Williams's).

Choice B is incorrect because "Williams'" is acceptable but "Williams's" is preferred. Choice C is incorrect because it lacks a possessive marker. Choice D is incorrect because "Williamss'" is not standard English.