The value of the integral \( \displaystyle \int_{0}^{1}\frac{\sqrt{x}\,dx}{(1+x)(1+3x)(3+x)} \) is:
\( \frac{\pi}{4}\left(1-\frac{\sqrt{3}}{2}\right) \)
\( \frac{\pi}{4}\left(1-\frac{\sqrt{3}}{6}\right) \)
\( \frac{\pi}{8}\left(1-\frac{\sqrt{3}}{6}\right) \)
\( \frac{\pi}{8}\left(1-\frac{\sqrt{3}}{2}\right) \)