If SEPLY is coded as RDOKX, then STICK is coded as

In a letter-coding question like this, every letter of the source word is replaced by shifting it a fixed number of positions along the alphabet, and the same shift is applied to every letter of the word, in the same left-to-right order.

1. Compare the given word SEPLY with its code RDOKX letter by letter: S to R, E to D, P to O, L to K, Y to X.

2. Convert each pair to alphabet positions to find the shift: S(19) to R(18), E(5) to D(4), P(16) to O(15), L(12) to K(11), Y(25) to X(24) - every letter moves back by exactly one position.

3. Apply this same one-position backward shift to each letter of STICK, in order: S(19) to R(18), T(20) to S(19), I(9) to H(8), C(3) to B(2), K(11) to J(10).

4. Write the shifted letters in the same order as STICK to get the coded word.

Since the -1 shift is confirmed independently by all five letters of SEPLY to RDOKX, not just one letter, and STICK has the same length, applying it uniformly is verified rather than assumed; a spot check on the last letter (K to J) still fits the same -1 pattern.

So STICK is coded as RSHBJ.