Which of the following is a good way to conserve electricity?

Recycling

Turn off the lights when they are not in use

Turning the shower, water hotter

Turning the air conditioner to a colder setting

Turning off the lights when they are not in use.

Are you sure

Yes, I am sure. Turning off the lights when they are not in use is a good way to conserve electricity as it reduces unnecessary energy consumption. Recycling, turning the shower water hotter, and turning the air conditioner to a colder setting do not directly relate to conserving electricity.