A line on a graph shows a proportional relationship between the weight, x, in pounds of apples purchased and the total cost y. Two points on the graph are located at (3, 3.21)(3, 3.21) and (5, 5.35)(5, 5.35).



What is the unit rate for the cost of the apples per pound?

A, $0.83 per lb

B, $1.07 per lb

C, $1.67 per lb

D, $1.76 per lb