Answer:
A. a time when Robespierre executed citizens for not being revolutionary enough
Step-by-step explanation:
The Reign of Terror was a period during the French Revolution that involved radicals like Robespierre, who led the Committee of Public Safety
The Reign of Terror involved thousands of executions by the guillotine due to revolutionary fervor and treason accusations.
People against the Revolution, or those that weren't revolutionary enough, were executed by Robespierre and his committee.
So, the correct answer is A