This is a test of commonsense with single/multi-choices. Complete the next sentence:

How to clean a biometric scanner
Disconnect the unit from the power source
Keep a soft cloth handy when you are about to start cleaning the scanning area.
Take care while lifting up and removing the front layer of the scanning area.
Remove the part where the finger is placed for scanning.

Options: +Oil the area with a residue remover. Splash water on the cloth until the oil is wiped off.; +Properly remove with a soft cloth, doing not touch the area it was placed for. Allow it to dry before touching the ground.; +Take care carefully as the broken finger will be located near to the area where the magnets attach. Then, carefully remove the tip the rest of the scanning area.; +Clean the area using a soft piece of cloth. If there are bigger dirt particles, try removing them using a light blower.;
The answer is:
Clean the area using a soft piece of cloth. If there are bigger dirt particles, try removing them using a light blower.