Let x have the density function $$f(x) = \begin{cases}\frac{3}{4}(1 - x^2) & if -1 \leq x \leq 1\\0 & otherwise \end{cases}$$. Then the probability $$p\left(\frac{-1}{2} \leq x \leq \frac{1}{2}\right)$$ is

A

68.75%

B

31.36%

C

95%

D

60.7%