A technician needs to troubleshoot a user's smartphone that will not connect to its wireless provider's service. Which of the following should the technician check first?

While a faulty SIM card can cause connection issues, verifying the active service plan is a more foundational and quicker initial check.

Network settings are important for connection, but confirming an active service plan is a prerequisite before delving into configuration specifics.

The subscription plan is the fundamental enabler for cellular service; checking it first can quickly determine if the issue is due to an inactive, suspended, or expired plan, an unpaid bill, or data limits before troubleshooting device-specific settings.

Bluetooth connection is used for short-range device pairing and is entirely unrelated to a smartphone's ability to connect to its wireless cellular provider's service.