1. 

In the following question find out the group of the letters in the place of question mark in the letter series.

H3M, I5O, L9S, Q17A, ?

A. X33Q
B. Z33P
C. X33P
D. W33R

Answer: Option A

Explanation:

Pattern of the series as shown below

letter-and-symbol-series-logical-reasoning-practice-level---letter-and symbol-series-problems

Hence, the missing term is X33Q.