The answer is C. Y= -1/5 x + 1.
Explanation: the slope of the data is negative since it is going down from left to right, and since in a linear equation slope is represented by mx (m being the rise over run) you can automatically kick out all the positive slopes. The +1 at the end is where the lime ontersepts the y axis, since it intersects at positive one you can knock out another answer. Now all you have to do is count the rise over the run. The line goes down by one and then to the right by 5, therefore c is the right answer