The answer is D. OQVW.
In each of the other options, the letters are in alphabetical order. In D, the letters are not in alphabetical order.
A. ACHI - A, C, H, I are in alphabetical order. B. DFKL - D, F, K, L are in alphabetical order. C. MNST - M, N, S, T are in alphabetical order. E. PRWX - P, R, W, X are in alphabetical order.
