Overall taking into account all the era's singles which had the best? Not including Glory since we don't know what the other single(s) will be.
My ranking
1. Femme Fatale
2. Oops!...I Did It Again
3. Circus
4. ...Baby One More Time
5. Britney Jean
6. Blackout
7. In the Zone
8. Britney (but it has my #1 favourite Britney single, Overprotected)
Don't judge my basic taste plz