If N is the sister of O and O is the father of P, what is the relationship of N to P?

A. AUNT

What letter should come next in the series: a, c, e, g, ?

B. H

Identify the missing letters in the series: m, o, q, s, ?

A. U

Complete the series: z, x, v, t, ?

A. R

What letter should replace the question mark in the series: b, d, f, h, ?

A. J