I’ll add to what’s been said above. People who work QA usually work with the people who are writing SOPs, change controls, etc. They’re in the office making sure that all of the paper work and paper trail are correct and follow regulation. They catch any issues and send it back for revision. QC people are usually on the floor, checking machinery and the production area. They’re familiar with the process and check to see whether things are they way they should be. If they aren’t, they bring it up and ensure that CAPAs/Quality Notifications are written so that someone will address the issue(s).