Consider the Op-Amp circuit shown in the figure.
If $V_{i}=V_{1} \sin (\omega t)$ and $V_{o}=V_{2} \sin (\omega t+\phi)$, then the minimum and maximum values of $\phi$ (in radians) are respectively
- $-\pi / 2$ and $\pi / 2$
- $0$ and $\pi / 2$
- $-\pi$ and $0$
- $-\pi / 2$ and $0$