MCQ
If $f(x)=\left\{\begin{array}{cc}\frac{x-4}{|x-4|}+a, & \text { for } x<4 \\ a+b, & \text { for } x=4 \\ \frac{x-4}{|x-4|}+b, & \text { for } x>4\end{array}\right.$
is continuous at $x=4$, then
is continuous at $x=4$, then
- A$a=1, b=1$
- ✓$a=1, b=-1$
- C$a=0, b=0$
- D$a=-1, b=1$