The local pizzeria is charging $12.50 for a medium pizza with no toppings. Each topping costs $1.20 each. The variable, P, to represent the price and the variable, t, to represent the number of toppings. Which of the following models is correct?

a) P = 12.50t + 1.20

b) P = 1.20t + 12.50

c) t = 12.50P + 1.20

d) t = 1.20P + 12.50