If $f$ is twice differentiable and $f''(0)=2$ then $\lim\limits_{x\to 0}\large\frac{2f(x)-3f(2x)+f(4x)}{x^2}$=

Question

$(a)\;6\qquad(b)\;3\qquad(c)\;12\qquad(d)\;None\;of\;these$