Final answer:
A carrier's safety plans in Alberta must incorporate vehicle maintenance, driver training and qualifications, and hours of service regulations, encompassing all the options listed in the query.
Step-by-step explanation:
In Alberta, a carrier's safety plans must address several critical areas to ensure both compliance with regulations and the safety of operations. Specifically, these plans must cover vehicle maintenance and inspections, driver training and qualifications, and hours of service. Therefore, the answer to the question is D) All of the above. Each aspect plays a vital role: proper maintenance ensures the vehicles are safe to operate; comprehensive driver training and qualifications guarantee that drivers are competent and well-prepared; and adhering to regulated hours of service helps to prevent driver fatigue and maintain road safety.