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

Câu hỏi: Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
Higher education is very importance to national economies, and it is also a source of trained and educated personnel for the whole country.

A. economies

B. educated

C. the whole country

D. importance