In a code language, MONKEY is written as LPMLDZ. How will STROKE be written as in that language?

Decoding the pattern of MONKEY ->LPMLDZ

M is changed to L which is (n-1)th alphabet in the alphabetical order.

O is changed to P which is (n+1) of the alphabetical order.

N is changed to M which is (n-1)th alphabet of alphabetical order.

K is changed to K which is (n+1)th alphabet.

E is changed to D which is (n-1)th alphabet.

and Y is changed to Z which is (n+1)th alphabet.

so alternate (n-1)- (n+1) pattern is being followed starting from (n-1).

applying the same logic in STROKE 

S=>S-1 = R

T=> T+1 =U

R=>R-1=Q

O=>O+1=P

K=>K-1=J

E=> E+1=F

Hence RUQPJF is the right answer which is option D