RUBBER _______ FROM VULCANIZED SILICONES WITH A HIGH MOLECULAR WEI...

48. - 2 DE THI THU DH MON THI TIENG ANH VA DAP AN
Tiếng Anh 2 DE THI THU DH MON THI TIENG ANH VA DAP AN

48. Rubber _______ from vulcanized silicones with a high molecular weight is difficult to distinguish from natural

rubber.

A. is produced

B. producing

C. that produces

D. produced