When are you allowed to pass another vehicle to its left?

Answer: B — When a police officer has directed you to

Passing another vehicle to its left is generally not permitted in most situations because it can create unsafe conditions, especially if the vehicle you are passing is making or preparing to make a left turn. However, the presence of a police officer directing traffic indicates that certain rules may be temporarily altered for safety or traffic management purposes. In this context, following a police officer's directions allows for exceptions to standard traffic laws. Therefore, if a police officer instructs you to pass another vehicle on its left, it is considered acceptable because their role is to manage traffic flow and ensure safety during unique situations. The other choices do not align with the rules of the road. Being in a hurry does not justify unsafe driving behavior, passing when no other vehicles are around may still be illegal in certain contexts, and feeling that it is safe is subjective and does not automatically meet legal or safety requirements. Thus, following the police officer's direction is the identified legal and safe scenario for passing on the left.