Mark the letter A, B, C or D to indicate the underlined part that needs correction in each of the following questions.

Viet Nam was the first lndochinese country joining ASEAN, and its move helped end confrontation between the lndochinese party and ASEAN.

A. was        

B. joining    

C. confrontation   

D. its move

Vì sao dòng điện trong hồ quang điện lại chủ yếu là dòng electron chạy từ catot đến anot?