Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
Yesterday I met your brother, ______ had taken us to the Headquarters of the United Nations in New York before.
A. that
B. whom
C. whose
D. who
Chọn D
“who” là mệnh đề quan hệ, thay thế cho “your brother” ở vế trước