1) QJ
2) QL
3) QI
4) QK
5) OJ
6) OI
7) OK
8) PK
9) PI
10) None of these
Solution
The first letter of the given series is formed by adding 2 letters
So H+2 = J, J+2 = L, L+2= N, N+2 = P
2nd letter is formed in the revers direction by subtracting 4 letters
So Y - 4 = U, U - 4 = Q, Q - 4 = M, M - 4 = I