About Checks before driving off: seat, headrest, wheel, mirrors and seatbelt: which statement is WRONG?
The seatbelt is only mandatory on the motorway, or at higher speeds.
The headrest must sit flat behind your head; this gives you the best protection in a rear-end collision.
The text lists the order seat, headrest, steering wheel and mirrors, and only then 'and of course you put on your seatbelt before departure' as the last step.
The text literally says: check before EVERY trip.
Explanation
trap: speed-as-condition. You put on your seatbelt before driving off, with no exception for road type or speed. The seatbelt duty applies just as much in the city as on the motorway