The correct option is B 0
We know that |x|=x for all x≥0 and |x|=−x for all x<0. Therefore,
At x=2,
|x−1|=x−1 and |x−3|=−(x−3)=−x+3
⇒f(x)=(x−1)+(−x+3)=2
which is a constant function and the derivative of a constant function is always zero. So at x=2 derivative of f(x) is zero.