Which of the following describes the root cause of the issue?

A technician is attempting to resolve an issue with a customer’s smartphone. The customer can no longer unlock the smartphone due to an “incorrect pattern" message appearing onscreen, The customer explains that the option to "make pattern visible” is unchecked in the security settings. The customer has also unsuccessfully tried to unlock the smartphone using a PIN. The customer is certain the pattern and PIN being entered are both correct. The technician is unable to click the proper options onscreen to perform a reset, but can select it without issue using the side buttons designed for volume and power .

Which of the following describes the root cause of the issue?
A . The smartphone’s data cable is disconnected.
B . The smartphone’s side buttons are becoming sticky.
C . The smartphone has very little free space available.
D . The smartphone screen needs to be calibrated.

Answer: A