What type of smart card does John use if he waves it near a card reader for access?

The correct answer highlights the nature of contactless smart cards. When John waves his card near a reader, this indicates that he is using a contactless smart card. Contactless smart cards utilize RFID (Radio Frequency Identification) technology, allowing users to simply hold the card near a reader without needing to insert it physically. This method is designed for convenience and speed, particularly in access control scenarios like entry to buildings or transit systems.

Though the answer suggested that both contact and contactless functionalities apply, in this specific context—where the card is waved (and not inserted)—it specifically identifies that he is using the contactless feature. There’s no indication that he used the contact method during this interaction, making this interpretation slightly misleading. A contact smart card, on the other hand, requires direct contact with a reader, which is not what occurred here.

Thus, the response that John is using a contactless smart card effectively encapsulates the intended functionality of the action he performed, reinforcing the distinct differences between contact and contactless methods in smart card technology.