Answer:
D. 4
Step-by-step explanation:
We have been given graph of a function. We are asked to choose the value, which is input of the given function.
We know that input of a function is value of the independent variable. Upon looking at our given graph, we can see that x is independent variable.
All the values in domain of our a function will be input values.
We can see that domain of our given function is [tex][1,\infty)[/tex].
Our function is defined for x values that are greater than or equal to 1, so first three options are not correct choice.
Since our function is defined at [tex]x=4[/tex], therefore, 4 is an input of the given function.
