FILE is written as DKJG in a certain code language. How will RAIL be written as in that language?

FILE $$\rightarrow$$ DKJG

RAIL $$\rightarrow$$ ? 

Logic: Each letter is decreasing and increasing alternatively - 2, and + 2.

F - 2 = D

I + 2 = K

L - 2 = J

E + 2 = G

R - 2 = P

A + 2 = C

I - 2 = G

L + 2 = N

So, RAIL will be written as PCGN.

Hence, the correct answer is (D) PCGN.