A car's gas mileage is increased and the engine has less power. An airplane uses a more efficient engine and has higher performance. A sports drink's taste is improved and has the same nutritional content. A computer company upgrades the hardware and the price remains unchanged.
I gave my students this multiple choice question: In the design process, a trade-off occurs when a problem is solved but a feature is sacrificed. Which of the following is an example of a trade-off?

Only one answer is correct among these 4 choices:
- A car's gas mileage is increased and the engine has less power.
- An airplane uses a more efficient engine and has higher performance.
- A sports drink's taste is improved and has the same nutritional content.
- A computer company upgrades the hardware and the price remains unchanged.

Could you tell me which one is correct?

A car's gas mileage is increased and the engine has less power.