Suppose the cubic ${x^3} - px + q$ has three distinct real roots where $p>0$ and $q>0$. Then which one of the following holds?

Question

Suppose the cubic ${x^3} - px + q$ has three distinct real roots
where $p>0$ and $q>0$. Then which one of the following holds?

The cubic has minima at $\sqrt {{p \over 3}} $ and maxima at $-\sqrt {{p \over 3}} $

The cubic has minima at $-\sqrt {{p \over 3}} $ and maxima at $\sqrt {{p \over 3}} $

The cubic has minima at both $\sqrt {{p \over 3}} $ and $-\sqrt {{p \over 3}} $

The cubic has maxima at both $\sqrt {{p \over 3}} $ and $-\sqrt {{p \over 3}} $

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