PLZZZZZZZZZZZZZZ HURRYYY ..The graph represents the serving sizes of chow mein at a local restaurant. Which of these describes the unit rate? *
A: (5, 1250) where 1250 is the unit rate
B: (3, 750) where 3 is the unit rate
C: (1, 250) where 250 is the unit rate
D: (7, 1750) where 7 is the unit rate