I'm towing a tent trailer and I've heard connecting your break away switch to the body of the vehicle and I've heard connecting it to the hitch. Does anyone have a solid answer and explain it to me?

There are some good answers here:

https://forums.goodsamclub.com/index.cfm/fuseaction/thread/tid/22682781/gotomsg/22690287.cfm

Hitch no. Hitch can come undone.