electric car digital camera high-speed Internet battery-powered radio
I gave my students this multiple choice question: Some research has shown that the burning of fossil fuels contributes to an effect called global warming, which scientists believe is changing the chemical makeup of Earth's atmosphere. Use of which invention would help lower this effect?

Only one answer is correct among these 4 choices:
- electric car
- digital camera
- high-speed Internet
- battery-powered radio

Could you tell me which one is correct?

electric car