What feature must an automatic dispenser include for authorization?

Answer: B — key, card, or code system

An automatic dispenser must include a key, card, or code system for authorization to ensure that only authorized individuals can access and operate the dispensing equipment. This system provides a straightforward and effective means of verification, allowing users to prove their identity before dispensing fuel. By requiring a physical key, a specific card, or a personalized code, the dispenser can control access and maintain security, reducing the risk of unauthorized usage and potential hazards associated with the dispensing of compressed natural gas. Other potential options like facial recognition technology may offer a modern approach to authorization but are not universally implemented across all dispensers, nor do they guarantee security and ease of use like a key, card, or code system does. Similarly, a manual override or remote control would not serve the same purpose of ensuring validated user access, as they do not inherently include a systematic verification process for authorized usage.