Final answer:
The incorrect rule is that drivers must yield to vehicles coming from the left at an intersection without signals or signs; typically, the right-of-way is given to the vehicle that arrives first or to the vehicle on the right if they arrive simultaneously.
Step-by-step explanation:
Among the provided right-of-way rules, the one that is NOT true is: b) At an intersection where there is no stop sign, yield sign or oncoming traffic signal, drivers must yield to vehicles coming from the left. Typically, the right-of-way at intersections without signs or signals is governed by specific laws which vary from place to place. In many jurisdictions, drivers are required to yield to the vehicle that arrives first, or to the vehicle on the right if both arrive at the same time, not necessarily to the vehicle on the left.
As for the other options: a) You must obey signals given by a law enforcement officer, even if the officer's signals contradict the traffic signals - this is indeed true as an officer has the authority to override traffic signals. c) Drivers must yield the right-of-way at all times to pedestrians who are in a marked or unmarked crosswalk - this rule ensures pedestrian safety and is commonly enforced. Finally, d) Pedestrians using a guide dog or carrying a white cane have absolute right-of-way - this is generally true and is a part of regulations protecting individuals with visual impairments.