A scatter plot is shown with a line of fit sketched through the data. A scatter plot contains the ordered pairs 1,2 and 2,5 and 3,3 and 5,6 and 6,4 and 7,6 and 8,4 and 9,7.5 and 10,4.5. A linear function is drawn with a y-intercept of 3 and a slope of one-third. Choose the set of coordinates that would best be used to calculate the slope of the line of fit.
a) (1, 2) and (10, 4.5)
b) (2, 5) and (9, 7.5)
c) (3, 4) and (10, 6)
d) (3, 3) and (8, 4)