The correct answer is 10 AM. • If any Members of Parliament want to raise any matters during the Zero Hour, He or She must give the notice before 10 am to the Speaker/ Chairman on the day of the sitting in the House. Explanation & Key Takeaways: • Zero Hour was introduced in the Parliament in 1962. It is the time when Members of Parliament (MPs) can raise an Issue of Urgent Public Importance. • The time of Zero Hour starts at 12 noon immediately following the Question Hour in the Parliament. • The Notice must state the Subject they wish to Raise the issue in any of the Houses. However, the Speaker of Lok Sabha or Chairman of Rajya Sabha may Allow or Decline a Member to raise a matter of importance regarding public issues. • It is not mentioned in the Rules of Procedure Book of Parliament. Thus, it is an Informal subject available to Members of Parliament to Raise issues without any notice period 10 days in advance. This is because, generally, the Matters are of Public Importance cannot wait for 10 days in the Parliament. Related Concepts: • In 1962, Rabi Ray (Ninth Speaker of Lok Sabha) introduced this Zero Hour.