Answer
$C$
Work Step by Step
The secant function is undefined when $x=-\frac{\pi}{2}, \frac{\pi}{2}, \frac{3\pi}{2}, ...$
Thus, its graph has the vertical asymptotes $x=-\frac{\pi}{2}, \frac{\pi}{2}, \frac{3\pi}{2},...$.
This means that the possible graphs of $y=-\sec{x}$ are the ones in Options $A$ and $C$.
Note that when $x=0$ , the value of $y=-\sec{x}$ is $-1$.
Only the graph in Option $C$ satisfies this.
Thus, the graph of $y=-\sec{x}$ must be the one in Option $C$.
