For which of the following curves, the line \(x+\sqrt{3}\,y=2\sqrt{3}\) is the tangent at the point \(\left(\dfrac{3\sqrt{3}}{2},\dfrac{1}{2}\right)\)?
\(y^{2}=\dfrac{1}{6\sqrt{3}}\,x\)
\(x^{2}+9y^{2}=9\)
\(2x^{2}-18y^{2}=9\)
\(x^{2}+y^{2}=7\)