Đáp án tham khảo B D D D A C D A C 10 B 11 D 19 D 20 D 28 C 37 A 46 C 29 B 38 C 12 B 21 D 30 B 39 C 47 B 48 B 13 B 14 D 15 B 16 D 22 D 23 A 24 B 25 D 26 C 31 A 32 A 33 A 34 C 35 A 40 B 41 A 49 A 50 A 42 A 43 A 44 D 17 C 27 A 36 C 45 C 18 A