What drives do I erase on my MacBook Air?

Hi. I am trading in a MacBook Air (early 2015). I received the trade-in kit with a sheet telling me to erase my hard drive (it's an SSD). It just talks about it as if it's one drive. It then says to reinstall MacOS.

I just want to make sure I'm doing this right. The Disk Utility shows two internal drives - Macintosh HD and Macintosh HD-Data. It also shows a disk image for macOS Base System. Am I supposed to erase all 3 of those? If not, which one or ones do I erase?

Thanks!