The correct answer is A. Buying a new car.
Explanation
The budget is a term referring to the amount of money that is going to be spent on something determined as a trip, a ride, a car, studies, housing, food among others. Additionally, it is common budgets are modified or adjusted over time as you might want to spend less or more money for a specific purpose. In the case of Chiaki, she wants to reduce the amount of money she spends on gas every month which means she needs actions to adjust her budget.
In this context, walking to work, carpooling and riding the bus are all actions that would help her with the purpose as all of these are cheaper than using your own car. However, if she buys a new car her budget is likely to increase because of the amount of money she needs to buy the new car and extra money she will need to pay if the car requires more gas. So, the correct answer is A. Buying a new car.
