Mechanical Comprehension

1 A 20 A 39 A 2 B 21 A 40 B 3 B 22 A 41 A 4 A 23 B 42 A 5 A 24 C 43 B 6 B 25 A 44 A 7 C 26 B 45 B 8 C 27 A 46 C 9 B 28 A 47 A 10 A 29 C 48 B 11 A 30 B 12 B 31 A 13 B 32 C 14 B 15 A 53 A 16 B 54 B 17 B 55 C 18 A 37 B 56 B 19 B 38 A