Short answer: Prefer Remove; use Quarantine if unsure.
How to decide
Remove when the item is clearly malicious or unwanted (adware, trojan, SMS fraud, etc.).
Quarantine if you are not sure what the file is, or it belongs to an app you still use.
After you choose
Remove: The item is deleted. If it returns, update definitions and run Deep scan.
Quarantine: The item is isolated and can’t run. Review later via Quarantine.
Special cases
Preinstalled or device-admin apps: Android may block removal. Go to App info → Disable or Remove admin first.
System locations: Some files are read-only; the app will recommend quarantine or manual steps.
Good practice
Keep Quarantine cleanup at 2–4 weeks.
Avoid Ignore unless you know the exact file and trust its source.