Let \(\vec{\alpha}, \vec{\beta}, \vec{\gamma}\) be three non-zero vectors which are pairwise non-collinear. If \(\vec{\alpha}+3 \vec{\beta}\) is collinear with \(\vec{\gamma}\) and \(\vec{\beta}+2 \vec{\gamma}\) is collinear with \(\vec{\alpha}\), then \(\vec{\alpha}+3 \vec{\beta}+6 \vec{\gamma}\) is
(A) \(\vec{\gamma}\)
(B) \(\overrightarrow{0}\)
(C) \(\vec{\alpha}+\vec{\gamma}\)
(D) \(\vec{\alpha}\)