正解:A
MMS (Multimedia Messaging Service) is a type of text message that can include images, videos, audio, or other media files. Unlike SMS (Short Message Service), which only uses cellular networks, MMS requires mobile data service to send and receive messages. Therefore, if the mobile data service is disabled on the smartphone, the user will not be able to send or receive MMS messages, even if they can make and receive voice calls using the cellular network.
Reference
* What is MMS messaging? How to send and receive MMS messages on your iPhone or Android device
* Why Can't I Send or Receive MMS Messages?
* The Official CompTIA A+ Core 1 Student Guide (Exam 220-1101), page 349