YOU CAN CHOOSE TO TAKE PART IN OUTDOORS ACITIVITIES OR NOT. THEY A...

15. - BAI KIEM TRA SO 1 MON TIENG ANH 9
BAI KIEM TRA SO 1 MON TIENG ANH 9

15. You can choose to take part in outdoors acitivities or not. They are _____.

A. compulsory

B. required

C. optional

D. necessary