The question is based on alphabetical code, where each letter derives its code from a certain pattern. In the given code `BJP` is `DMK`, implying B is coded as D, J as M, and P as K. If we look at the alphabets` placements, B to D is a shift of two positions forward, J to M is a shift of 3 positions forward, and P to K is a shift of -5 positions (or in other words a shift of 21 positions forward if we start from the beginning again after Z).

Applying this pattern to `RRS`, we get T (2 positions forward from R), W (3 positions forward from R), and N (21 positions forward from S, starting from the beginning after Z), which results in `TWN`. So, `TWN` is the alphabetical code for `RRS`.

Options 1: `CPI`, 3: `SJP`, and 4: `TDP` are incorrect as they don`t follow this pattern. Therefore, the correct answer is option 2: `TWN`.