Let $$f(x) = \begin{cases}x^2 \mid \cos \frac{\pi}{x} \mid & x \neq 0\\0, & x = 0\end{cases}, x \in R$$, then f is

A

differentiable both at x = 0 andat x = 2

B

differentiable at x = 0 but not differentiable at x = 2

C

not differentiable at x = 0 butdifferentiable at x = 2

D

differentiable neither at x = 0 nor at x =2