Devante has a lunch account in the school cafeteria His starting balance at the beginning of the month is $35.50. The first wook, Davante bought 3 lunches and his account balance was $28.00. The second week. Devante bought 5 lunches and his account balance was 515 50
In a model that relates the balance of his lunch account as a function of the number of lunches he buys, what does the rate of change represent?

A: the number of lunches he purchases

B: the starting balance of his lunch account

C: the amount of money in his lunch account

D: the amount of money he pays for each lunch