问题
已知，矩阵 $\boldsymbol{A}$ $=$ $\left(a_{i j}\right)_{m \times n}$, $\lambda$ 为实数.则，$\lambda \boldsymbol{A}$ $=$ $?$
选项
[A]. $\lambda \boldsymbol{A}$ $=$ $\left(\begin{array}{ccc} \frac{1}{\lambda} a_{11} & \cdots & \frac{1}{\lambda} a_{1 n} \\ \vdots & & \vdots \\ \frac{1}{\lambda} a_{m 1} & \cdots & \frac{1}{\lambda} a_{m n} \end{array}\right)$[B]. $\lambda \boldsymbol{A}$ $=$ $\left(\begin{array}{ccc} \lambda a_{11} & \cdots & a_{1 n} \\ \vdots & & \vdots \\ \lambda a_{m 1} & \cdots & a_{m n} \end{array}\right)$
[C]. $\lambda \boldsymbol{A}$ $=$ $\left(\begin{array}{ccc} \lambda a_{11} & \cdots & \lambda a_{1 n} \\ \vdots & & \vdots \\ a_{m 1} & \cdots & a_{m n} \end{array}\right)$
[D]. $\lambda \boldsymbol{A}$ $=$ $\left(\begin{array}{ccc} \lambda a_{11} & \cdots & \lambda a_{1 n} \\ \vdots & & \vdots \\ \lambda a_{m 1} & \cdots & \lambda a_{m n} \end{array}\right)$
$\textcolor{orange}{\lambda} \boldsymbol{A}$ $=$ $\left(\textcolor{orange}{\lambda} a_{i j}\right)_{m \times n}$ $=$ $\left(\begin{array}{ccc} \textcolor{orange}{\lambda} a_{11} & \cdots & \textcolor{orange}{\lambda} a_{1 n} \\ \vdots & & \vdots \\ \textcolor{orange}{\lambda} a_{m 1} & \cdots & \textcolor{orange}{\lambda} a_{m n} \end{array}\right)$