In the sequence A, B, C, ?, E, F, what character should replace the question mark?

A. D

Find the missing character in the series: M, N, O, ?, Q, R.

A. P

In a pattern of symbols: ?, ???, ?????, ?, ????????. What is the missing symbol?

C. ???????

In the series X, Y, Z, A, ?, C, D, what character should fill the gap?

A. B

In the sequence A, B, C, D, ?, F, G, what character should replace the question mark?

A. E