What step did the government take to stop demonstrations?

Correct answer: Imposed curfew

The correct answer is C, imposed curfew. A curfew restricts people from moving or gathering in public during specified hours, so authorities use it as a coercive measure to limit demonstrations and regain control of streets. In Petrograd, the government attempted to contain the growing unrest through such restrictions, but repression did not remove the underlying causes: food shortages, wartime hardship, factory conflict and opposition to Tsarist rule. Distributing land, raising wages and holding an election would have been policy or reform measures, not the immediate restrictive response described here. The important concept is that repression can temporarily limit public activity but may intensify anger when grievances remain unresolved.