Answer:
C
Step-by-step explanation:
With the domain, we are talking about the values on the y- axis. f(x) = y.
What this means is that you want to concentrate on the outcome of f(x) for all valid x values.
Since the SQRT can never be negative, you can NOT input an x value that is negative. So by that alone you can exclude answers A and B.
The SQRT for the value of x=0 is allowed and so are all positive numbers of x. Hence answer C is correct (and andwer D is also false).
By the way, in the graph you can see that for x=0 the resulting function outcome of f(0) = 3. This defines the point (0,3) on the graph of this square root function.
