Find All Critical Numbers for the Function $f(x)=x-\frac{10}{x}$ A) Local Maximum At

Multiple Choice

Find all critical numbers for the function. State whether it leads to a local maximum, a local minimum, or neither.
- $f(x) =x-\frac{10}{x}$

A) Local maximum at $\sqrt{10}$ ; local minimum at $-\sqrt{10}$
B) Local maximum at -10 ; local minimum at 10
C) Local maximum at $-\sqrt{10}$ ; local minimum at $\sqrt{10}$
D) No critical numbers; no local extrema