The code replaces each letter by its opposite in the alphabet (A becomes Z, B becomes Y, and so on): T to G, A to Z, B to Y, L to O, E to V, which matches GZYOV. Applying the same reversal to CHAIR: C to X, H to S, A to Z, I to R, R to I, giving XSZRI. The other options misplace one or more of these opposite letters. The correct option is 'XSZRI'.