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

• The law requires cyclists or passengers on a bicycle, who are under 18 years of age, to wear an approved bicycle safety helmet.
  Explanation:

  "The law requires cyclists or passengers on a bicycle, who are under 18 years of age, to wear an approved bicycle safety helmet."
• The law requires cyclists or passengers on a bicycle, who are under 18 years of age, to drive without a helmet.
• The law requires cyclists or passengers on a bicycle to wear a helmet if they want.
• All of the above.