\({[M{L^{ - 1}}{T^{ - 2}}]^x}{[M{T^{ - 3}}]^y}{[L{T^{ - 1}}]^z} = {[MLT]^0}\)
By comparing the power of \(M, L, T\) in both sides
\(x + y = 0\) .....\((i)\)
\( - x + z = 0\) .....\((ii)\)
\( - 2x - 3y - z = 0\) …\((iii)\)
The only values of \(x,\,y,\,z\) satisfying \((i),\) \((ii)\) and \((iii)\) corresponds to \((b).\)