The graph below shows a line of best fit for data collected on the amount customers spent in relation to the discount they received. The equation of the line of best fit is y = 25x + 7.5. What does the y-intercept represent?

A.
the discount received by a customer who did not make a purchase

B.
the discount per item

C.
the amount spent by a customer who did not receive a discount

D.
the number of items purchased