In $2019,$ the U$.$S$.$ Food and Drug Administration $($FDA$)$ issued an advisory for patients with Medtronic implantable defibrillators. The patients were using wireless telemetry functions. Why was the advisory issued?

The devices were found not to use encryption, authentication, or authorization.

The devices had been attacked, and sensitive patient data was being stolen from the devices.

The telemetry data was being uploaded to the wrong site.

The telemetry was being encrypted, and the key pair had to be exchanged.