How are the internal components of a computer protected against ESD?

How are the internal components of a computer protected against ESD?

• by using computer cases made out of plastic or aluminum
• by unplugging the computer after use
• by grounding the internal components via attachment to the case
• by using multiple fans to move warm air through the case
  

  Answers Explanation & Hints: Electrostatic discharge (ESD) can occur when there is a buildup of an electric charge (static electricity) on a surface which comes into contact with another. This can be mitigated by grounding the internal components of the computer to the case.