find the points on the graph at which the tangent line is horizontal.

For the function, find the points on the graph at which the tangent line is horizontal. y= x - 5 Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. The point(s) at which the tangent line is horizontal is(are) (Type an ordered pair. Use a comma to separate answers as needed.) O B. The tangent line is horizontal at all points of the graph. O C. There are no points on the graph where the tangent line is horizontal