The graph shown below expresses a radical function that can be written in the form f(x) = a(x+k)
+c. What does the graph tell you about the
value of c in this function?

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.