Answer:
The correct option is D) x is all real numbers.
Explanation:
Consider the provided graph.
The provided graph is a horizontal line parallel to x axis.
where the equation of the graph is y=-3
The domain of a function is the set of all x values which a function can take.
Here, we can see that for every value of x the function gives the constant value which is -3.
Thus, the function is continuous at everywhere.
Therefore the domain of the function is all real number.
Hence, the correct option is D) x is all real numbers.