Which of the following is a phone service available to advise rescuers about hazardous materials?

The choice of CANUTEC as the service available to advise rescuers about hazardous materials is appropriate because CANUTEC is specifically designed to provide information and advice on how to safely manage hazardous materials incidents. It is a Canadian service that offers expertise 24/7 on hazardous substances, including guidance on containment, cleanup, and the appropriate protective measures that rescuers should take when dealing with chemical emergencies.

While the other services listed can be valuable in various emergency situations, they do not specialize in hazardous materials advice. For example, 9-1-1 is primarily a general emergency response number, the National Poison Control Center focuses on poisoning incidents that may not necessarily include hazardous materials, and the Emergency Operations Center provides coordination during emergencies but is not specifically tailored to hazardous materials situations. Therefore, CANUTEC is the appropriate choice for rescuers seeking expert guidance on hazardous materials.