Okay, here we have this:
We need to find the function corresponding to the graph, let's do it:
Firt we are going to find the slope:
m=(0-4)/(6-0)=-4/6=-2/3
And we can see in the graph that the y intersection is b=4.
So, according with this the equation of the line is:
y=mx+b
y=-2/3x+4
Finally we obtain that the correct answer is the option B.