Chapter 7, Conic Sections - Section 7.3 - Hyperbolas - 7.3 Exercises - Page 585: 5

The equation matches with the graph labeled as III.

Hyperbola with a horizontal transverse axis: $\frac{x^2}{a^2}-\frac{y^2}{b^2}=1$ $\frac{x^2}{4}-\frac{y^2}{1}=1$ $a^2=4$ $a=2$ Vertices: $(±a,0)=(±2,0)$ The hyperbole with vertices in $(±2,0)$ is the graph labeled as III.