Panneaux routiers

A 'No Standing' sign posted along a roadway means:

Panneau routier de Ontario — You may not stop your vehicle in this area except while loading or unloading passengers
Afficher la réponse et l'explication
Bonne réponse : B. You may not stop your vehicle in this area except while loading or unloading passengers

'No Standing' is a middle-level restriction: you can halt briefly only while actively loading or unloading passengers. Stopping to wait for someone or leaving the vehicle unattended is not permitted — that is what makes it stricter than 'No Parking'.