In the series: 1, 4, 9, ?, 25, what number should replace the question mark?

A. 16

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

C. ???????

In a series of numbers: 2, 4, 8, 16, ?, 64. What is the missing number?

B. 32

In a sequence of letters: A, C, E, G, ?, K. What is the missing letter?

B. H

What character should replace the question mark in the sequence: A, B, C, ?, E?

A. D