Answer:
C. He can turn off the touchpad in Windows.
Step-by-step explanation:
Option A is not correct. Connecting a touch screen monitor is not a solution as Henry has no problem with his monitor.
Option B is not correct. Attaching a USB mouse is not a solution as the mouse can also be moved mistakenly thereby causing probability for mistake.
Option C is correct. Turning off the touchpad from the windows will make Henry to avoid making such mistakes.
Option D is not correct. Putting a sheet of paper over the touchpad is not a solution as the paper can be easily moved and the paper contact with the mouse can cause mistake.