Answer
II quadrant.
Work Step by Step
We know that $\sin\theta = \frac{y}{R}$ and $\cos\theta = \frac{x}{R}$, where $R$ is always $R>0$.
So if $\sin\theta$ is positive. It means that $y>0$. It's true for I and II quadrants.
$\cos\theta$ is negative сonsequently $x<0$. It's right for II and III quadrants.
Both conditions are true only for II quadrant.
