If \[\mathbf{lo}{{\mathbf{g}}_{\mathbf{a}}}\mathbf{(ab)=x,}\] then \[\mathbf{lo}{{\mathbf{g}}_{\mathbf{b}}}\](ab) is:

• A.  \[\frac{1}{x}\]                         
• B.  \[\frac{x}{x+1}\]
• C.  \[\frac{x}{1-x}\]                       
• D.  \[\frac{x}{x-1}\]