Answer:
B
Step-by-step explanation:
Since we are given that f(x)=1, we just have to find what value of x gives 1 as the result.
From the graph, we can see that (0,1) gives 1 as a y-value. Thus, when x is 0, y is 1.
Therefore, f(0)=1.
So, our answer is B.
And we're done!