Complete the series: B, D, F, H, ?

A. J

Find the odd one out in the series: A, C, E, G, I, K, M, N

D. N

Identify the missing letters in the series: a, e, i, o, ?

A. U

What is the missing term in the series: 3, 6, 11, 18, ?, 42?

B. 26

Find the missing letter in the series: b, d, f, h, ?

A. J