Which of the following is equal to \[{{\mathbf{x}}^{\mathbf{3}}}\left( \mathbf{a}-\mathbf{2b} \right)+{{\mathbf{x}}^{\mathbf{2}}}\left( \mathbf{a}-\mathbf{2b} \right).\]

• A.  \[{{x}^{2}}(a-2b)(x+1)\] 
• B.  \[\left( {{x}^{2}}-1 \right)\left( a-2b \right)\]
• C.  \[\left( {{x}^{2}}+1 \right)\left( a-2b \right)\left( x+1 \right)\]                     
• D.  \[x\left( a-2b \right)\left( x-1 \right)\]