Helen’sister earns less money than she does

Câu hỏi: Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions.
Helen'sister earns less money than she does
A. Helen doesn't earn as much money as her sister
B. Helen's sister earns less money than she does
C. Helen earns more money than her boss
D. Helen's sister doesn't earn as much as she does