Cho hàm số $f\left( x \right)$ và \(g\left( x \r...

Câu hỏi: Cho hàm số $f\left( x \right)$ và $g\left( x \right)$ có $\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,f\left( x \right)=L,\,\,\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,g\left( x \right)=M.$ Khẳng định nào sau đây là đúng?

A $\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,\left| f\left( x \right)+g\left( x \right) \right|=\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,\left| f\left( x \right) \right|+\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,\left| g\left( x \right) \right|$            

B  $\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,\left| f\left( x \right)+g\left( x \right) \right|=\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,\left[ f\left( x \right)+g\left( x \right) \right]$

C   $\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,\left| f\left( x \right)+g\left( x \right) \right|=\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,f\left( x \right)+\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,g\left( x \right)$                                

D $\underset{x\to {{x}_{0}}}{\mathop{\lim }}\,\left| f\left( x \right)+g\left( x \right) \right|=\left| \underset{x\to {{x}_{0}}}{\mathop{\lim }}\,\left[ f\left( x \right)+g\left( x \right) \right] \right|$