On Fridays at the ballpark, a cup of soda costs $2, and each refill costs $0.80. If x represents the number of refills, which of the following equations represents the amount a person spends on soda?
A. y = 0.8x + 2
B. y = 0.8x + 2.8
C. y = 2x + 2.8
D. y = 2x + 0.8