Finish the following sentence with the best choice: To charge the battery of a smartphone,

Choices:
- you should plug a USB cable in a power supply, plug the supply in an outlet, plug the cable into the wireless charging pad and lay the phone on it.
- you should plug a USB cable in a power supply, plug the supply in an extension cord, and plug the other end of the USB cable directly into the phone.

Answer:
you should plug a USB cable in a power supply, plug the supply in an outlet, plug the cable into the wireless charging pad and lay the phone on it.