Where must a durable label for CNG fuel systems be located?

Answer: C — At the fueling connection receptacle

A durable label for CNG fuel systems must be located at the fueling connection receptacle to ensure that it is easily visible and accessible when refueling. This placement is critical for safety and compliance, as it allows fuel attendants, emergency responders, and vehicle operators to quickly identify the type of fuel being used and any pertinent safety warnings or instructions related to the CNG system. By locating the label at the fueling connection, it minimizes the risk of confusion during refueling and helps to promote the safe handling of compressed natural gas. While other locations such as the rear of the vehicle, the dashboard, or under the hood may provide some visibility, they do not offer the same level of immediate access and relevance during the refueling process, which is why the fueling connection receptacle is the most appropriate and effective position for the label.