Correct option is D

'GROWTH' is written as 'HQPVUG'
'FOUR' is written as 'GNVQ'
The following patterns are followed-
G → (+1) = H
R → (-1) = Q
O → (+1) = P
W → (-1) = V
T → (+1) = U
H → (-1) = G
And
F → (+1) = G
O → (-1) = N
U → (+1) = V
R → (-1) = Q
Similarly,
P → (+1) = Q
R → (-1) = Q
O → (+1) = P
B → (-1) = A
L → (+1) = M
E → (-1) = D
M → (+1) = N
S → (-1) = R
Thus, the code of 'PROBLEMS' is QQPAMDNR.