Determine the vertices and foci of the hyperbola $\frac{y^2}{4}-x^2=1$.

• A. Vertices: $\left(2,0\right),\left(-2,0\right)$Foci: $\left(\sqrt5,0\right),\left(-\sqrt5,0\right)$
• B. Vertices: $\left(0,2\right),\left(0,-2\right)$Foci: $\left(0,\sqrt5\right),\left(0,-\sqrt5\right)$
• C. Vertices: $\left(1,0\right),\left(-1,0\right)$Foci: $\left(5,0\right),\left(-5,0\right)$
• D. Vertices: $\left(0,1\right),\left(0,-1\right)$Foci: $\left(0,5\right),\left(0,-5\right)$