Mark the letter A, B, C, or D on you answer sheet...

Câu hỏi: Mark the letter A, B, C, or D on you answer sheet to indicate the word that differs from the rest in the position of the main stress in each of the following questions.

Emma and Karen used to be ______ good friends that I'm surprised they don't get on now.

A. such

B.enough

C. so

D. too