Time of zero-hour in Parliament is:

The answer is D. Zero Hour runs from 12 noon to 1 pm, immediately after Question Hour, which conventionally ends at 12 noon. Option D is printed as "1.00 am", which is a typo for 1.00 pm.

Zero Hour is an informal device, not a procedure written into the Rules of Procedure. Members use it to raise matters of urgent public importance without prior notice, and it is typically taken up after the listed business of the day. It began in the Lok Sabha in the early 1960s and was later adopted in other legislatures. The Speaker or Chairman has discretion over its timing, which is why the "time" is a convention rather than a fixed constitutional rule.

• A (9 to 10 am): Not a parliamentary slot. Sittings usually begin at 11 am.
• B (10 to 11 am): Also not a slot. This is the period before the House formally sits.
• C (11 am to 12 noon): This is Question Hour, the hour that precedes Zero Hour.

Core concept: parliamentary procedure and the difference between written rules and established practice. For Mains GS-II, it links to executive accountability and how Parliament scrutinises the government.

Trap: Aspirants often confuse Zero Hour with Question Hour and pick C. Remember that Question Hour comes first and Zero Hour follows it.