Here, the terms of the given series are a combination of letters and numerals, which have according to a set pattern.

1)

2, A, 9, B, 6, C, 13, D, ?


A) 9

B) 10

C) 12

D) 19

Answer:

Option B

Explanation:

The given sequence is a combination of two series :

l. 2, 9, 6, 13, ?  and  II. A, B, C, D

The pattern in I is : $2+7\rightarrow 9, 9-3\rightarrow 6, 6+7\rightarrow 13, 13-3\rightarrow 10$

So the missing term is 10.