A user reports that their smartphone frequently overheats and the battery drains much faster than normal. After confirming that there are no software issues and the device is updated to the latest firmware, which of the following is MOST likely the root cause of the problem?
The charger being used is not the manufacturer's original charger.
The device's screen brightness is set to maximum.
The battery needs to be replaced due to degraded health.
There is a large number of applications running in the background.