If the tangent at a point on the ellipse $\frac{x^2}{27} + \frac{y^2}{3} = 1$ meets the coordinate axes at $A$ and $B$, and $O$ is the origin, then the minimum area (in sq. units) of the triangle $OAB$ is:\\
(1) $\frac{9}{2}$\\
(2) $9$\\
(3) $9\sqrt{3}$\\
(4) $\frac{\sqrt{3}}{2}$