7, 10, 8, 11, 9, 12, ? Choose the correct choice from the following choices.
A) 9
B) 8
C) 11
D) 10
E) 15
D   10   This is a simple alternating addition and subtraction series. In the first pattern, 3 is added; in the second, 2 is subtracted.
<result>D</result>
7, 10, 8, 11, 9, 12, ?