Question

The graph shown below expresses a radical function that can be written in the form f(x)=a(x+k)^(1/n)+c.
pic attached
What does the graph tell you about the value of a in this function?.
A. a is greater than zero.
B. a is less than zero.
C. It is not possible to tell whether a is greater than or less than zero.
D. a = 1.