Final answer:
Under Alberta Hours of Service legislation, a driver is not allowed to drive when impaired, including impairment due to alcohol. Therefore, after consuming one alcoholic beverage, a driver is prohibited from driving.
Step-by-step explanation:
Under the Alberta Hours of Service legislation, a driver would not be allowed to drive when fatigued or impaired, which includes impairment due to alcohol consumption. So according to the options provided, a driver would not be allowed to drive after consuming one alcoholic beverage due to the risk of impairment. The laws are designed to ensure that drivers are not operating a vehicle when they are not in full control of their faculties, which is crucial for both their safety and the safety of others on the road. While the Hours of Service legislation primarily governs the maximum driving hours and mandatory rest periods to prevent fatigue, it also encompasses regulations against driving while impaired, which includes impairment due to alcohol. Therefore, although the law regulates driving hours, the condition that would unequivocally prohibit driving is if the driver has consumed alcohol, making option d) the correct answer.