What is the law regarding cyclists or passengers on a bicycle?

• Cyclists or passengers under 18 years old must wear an approved bicycle safety helmet.
  Explanation:

  "The law requires all cyclists and bicycle passengers under the age of 18 to wear an approved bicycle safety helmet. This rule is in place to reduce the risk of head injuries and improve overall road safety."
• Cyclists or passengers under 18 years old can ride without a helmet.
• Wearing a helmet is optional for all cyclists and passengers.
• All of the above.