The correct option is B 122912
The coded number signifies the position of the alphabet in its reverse order of the alphabetical series (Z = 1, Y = 2, X = 3, W = 4, ..., A = 26)
M U S K → MUSK
14th 6th 8th 16th → 146816
Similarly,
Z E R O → ZERO
1st 22nd 9th 12th → 122912
Hence, option (B) is the correct answer.