Find a Bound on the Real Zeros of the Polynomial $$f ( x ) = x ^ { 4 } + 2 x ^ { 2 } - 3$$

Multiple Choice

Find a bound on the real zeros of the polynomial function.
- $$f ( x ) = x ^ { 4 } + 2 x ^ { 2 } - 3$$

A) $- 3$ and 3
B) $- 6$ and 6
C) $- 4$ and 4
D) $- 5$ and 5