What type of message does Twilio send to communicate with the end user?

Twilio primarily uses SMS text messages to communicate with end users, making this the correct answer. SMS is a popular messaging protocol due to its simplicity and wide adoption. Twilio facilitates sending and receiving SMS messages easily through its API, allowing businesses to engage customers quickly and effectively via text.

This approach is particularly advantageous for real-time notifications, alerts, and customer support interactions, as SMS messages are typically read promptly by recipients. Furthermore, the high open rates associated with SMS make it a reliable channel for reaching users.

While other options like email messages, pre-recorded phone calls, and push notifications may be utilized in different contexts for communication, they do not represent Twilio's primary method of interaction with end users, which emphasizes the flexibility and immediacy that SMS offers.