The correct answer is E. wear an ESD wrist strap.
An ESD wrist strap is a device that helps to prevent electrostatic discharge (ESD) from damaging electronic equipment. It works by connecting the user to a ground, which helps to dissipate any static electricity that may build up on the user’s body.
The other options are not as effective at preventing ESD damage. Placing your PC on a rubber mat can help to reduce the risk of ESD damage, but it is not as effective as wearing an ESD wrist strap. Wearing leather soled shoes can also help to reduce the risk of ESD damage, but it is not as effective as wearing an ESD wrist strap. Periodically touching a safe ground point on the PC to discharge yourself is not a reliable way to prevent ESD damage. Static electricity can build up on your body even if you do not touch anything, and it can discharge at any time.
Therefore, the best way to prevent damaging your PC with static electricity is to wear an ESD wrist strap.