Question: Under what condition is a Java Card applet triggered by the EVENT_UNFORMATTED_SMS_CB, according to 3GPP specifications for (U)SIM Application Programming Interface (API)?
Option 1: When the applet has registered to this event and an Envelope Cell Broadcast Download is received.
Option 2: Automatically upon installation of the applet on the (U)SIM, without requiring event registration.
Option 3: Only if the applet is set as the default for handling SMS CB (Cell Broadcast) messages.
Option 4: When the (U)SIM device is in roaming mode and receives a Cell Broadcast message.
Explanation: This correct answer reflects the conformance requirement, emphasizing that triggering the applet requires both registration to the event and the receipt of an Envelope Cell Broadcast Download, highlighting the importance of explicit event registration in managing how (U)SIM applets interact with incoming cell broadcast messages.