Answer:
D. f(x) exist for all real numbers where x ≤ -1 or x ≥ 1
Explanation:
You can't divide by 0 and
You can't have a negative squareroot.
So solve for when x=0 for the denominator,
and when is x<0 for the squareroot.
I think the answer is A. hope this helps
C, details that help readers visualize the settings better. A wouldn't work because it doesn't help the setting, B doesn't help the setting either and D would only add more confusion so UT would have to be C by process of elimination.