Nếu 

Câu hỏi: Nếu $\underset{x\to 1}{\lim }\frac{f\left(x\right)-5}{x-1}=2$ và $\underset{x\to 1}{\lim }\frac{g\left(x\right)-1}{x-1}=3$ thì $\underset{x\to 1}{\lim }\frac{\sqrt{f\left(x\right).g\left(x\right)+4}-3}{x-1}$ bằng

A.$\frac{17}{6}$

B.$\frac{23}{7}$

C.7

D.17