Answer: 3) The cost of gas in dollars
Explanation:
From the setup: "In the equation, C represents the cost in dollars." While I think both 3 and 4 are true, the answer they're looking for is 3.
2.95 is the cost per gallon, and G is the number of gallons. From the equation, C is the cost per gallons times the number of gallons - which is the amount you spend for the gas.