#### Answer

secant function or $y=\sec{x}$

#### Work Step by Step

The given graph could either be the basic secant function or the basic cosecant function.
The given graph has the vertical asymptotes $x=-\frac{3\pi}{2}, -\frac{\pi}{2}, \frac{\pi}{2}, \frac{3\pi}{2}$.
Since secant is the reciprocal of cosine, and since the cosine function is equal to $0$ for $x=-\frac{3\pi}{2}, -\frac{\pi}{2}, \frac{\pi}{2}, \frac{3\pi}{2}$, then the secant function is undefined when $x=-\frac{3\pi}{2}, -\frac{\pi}{2}, \frac{\pi}{2}$, $\frac{3\pi}{2}$.
Therefore ,the given graph must be the graph of the secant function.