What character should replace the question mark in the sequence 3, 6, 9, ?, 15?

C. 12

In the sequence 2, 4, 8, ?, 32, what is the missing number?

B. 16

In the sequence 3, 6, 9, ?, 15, what number should replace the question mark?

C. 12

Find the missing character in the series A1, B2, C3, ?, E5.

A. D4

If the pattern is 1, 2, 4, 7, ?, 16, what number should replace the question mark?

B. 11