What should come in place of? in the given series based on the English alphabetical order?
BSL, EUM, HWN, KYO,?

Given: 

BSL, EUM, HWN, KYO,?

Logic: +3
From BSL → EUM
1st letter: B + 3 = E
2nd letter: S + 2 = U
3rd letter: L + 1 = M
From EUM → HWN
1st letter: E + 3 = H
2nd letter: U + 2 = W
3rd letter: M + 1 = N
From HWN → KYO
1st letter: H + 3 = K
2nd letter: W + 2 = Y
3rd letter: N + 1 = O
Now, KYO → ?
Apply the same logic:
1st letter: K + 3 = N
2nd letter: Y + 2 = A (Y + 2 wraps around to A)
3rd letter: O + 1 = P
Correct answer is (d) NAP.​​