​In a certain code language, REGULATION is written as QDFTKZSHNM. How will SYMPOSIUM be written as in that language?​

In a certain code language:

REGULATION is written as QDFTKZSHNM.

Logic: Each letter in the word is shifted one letter back in the alphabet to encode it.

R-1=Q, E-1=D, G-1=F, U-1=T, L-1=K, A-1=Z, T-1= S, I-1= H, O-1=N, N-1= M

S-1=R, Y-1= X, M-1=L, P-1=O, O-1=N, S-1=R, I-1= H, U-1=T, M-1=L

RXLONRHTL, is the correct answer 

Thus, correct answer is (c) RXLONRHTL