Insert the missing number.
2, 6, 12, 20, 30, 42, 56, 72, 90 (....)  Choose the most appropriate option:
A) 110
B) 38
C) 72
D) 66
E) 19
Explanation:   The pattern is 1 x 2, 2 x 3, 3 x 4, 4 x 5, 5 x 6, 6 x 7, 7 x 8,8 x 9, 9 x 10.   So, the next number is 10 x 11 = 110.   110nswer: 110) 110
<result>A</result>
Insert the missing number.
2, 6, 12, 20, 30, 42, 56, 72, 90 (....)