Sarah and Michelle bought pizza and lemonade for a party.
. Sarah bought 3 pizzas and 2 bottles of lemonade for $31.
• Michelle bought 2 pizzas and 4 bottles of lemonade for $30.
Which of the following systems of equations could be used to find p, the cost of one pizza, and b, the cost of a bottle of lemonade?

A. p + b = 31
p + b = 30

В. Зp + 2b = 30
2p + 4b = 31

C. 3p + 2b = 31
2p + 4b = 30

D. 5p + 6 = 61
p + b= 30 ​