IF $$A = \begin{bmatrix} 1 & 3 \\4 & 6 \end{bmatrix}, C = \begin{bmatrix} 2 & 1 \\ 1 & 1 \end{bmatrix}, B = \begin{bmatrix} b_{1} & b_{2} \\ b_{3} & b_{4} \end{bmatrix}$$ and BC =A, then $$\mid b_{1} \mid + \mid b_{4} \mid$$ = 

A

$$\mid b_{1} \mid + \mid b_{2} \mid$$

B

$$\mid b_{2} \mid + \mid b_{4} \mid$$

C

$$\mid b_{1} \mid . \mid b_{4} \mid$$

D

$$\mid b_{2} \mid \mid b_{3} \mid$$