Cho hàm số

Câu hỏi: Cho hàm số $f\left(x\right)=\frac{x-2}{x-1}$ Tính $f\text{'}\left(x\right)$ 

A. $f\text{'}\left(x\right)=\frac{1}{{(x-1)}^2}$

B. $f\text{'}\left(x\right)=\frac{2}{{(x-1)}^2}$

C. $f\text{'}\left(x\right)=\frac{-2}{{(x-1)}^2}$

D. $f\text{'}\left(x\right)=\frac{-1}{{(x-1)}^2}$