Answer:
the answer is D
Explanation:
because the number six just doesn't make sense in the other problems, here is the real explanation : 6 is in the ones place so like this: 1 2 3 4 5 6 and then keep going 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 (stop at 39 then keep going by tens like this to make it quicker: 40 50 60 70, and then by ones: 71 72 73 ' then. again, 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 and the by 10`s 110 120 130 140 150. And your done