Select the alphanumeric-cluster from among the given options that can replace the question mark (?) in the given series.
G7H, I9J, K11L, ?

Given: G7H, I9J, K11L, ?

Logic: Each letter increases by +2 in English alphabet and the number increases by +2.

First Letter Sequence: G → K → ?
G + 2→ I
I + 2 → K

K + 2 → M
Number Sequence: 7 → 9 → 11 → ?
7 + 2 → 9
9 + 2 → 11
11 + 2 → 13 
Third Letter Sequence: H → J → L → ?
H + 2 → J
J + 2 → L
L + 2 → N 
Thus, the correct option is (c)  M13N