Correct answer: B. Crisis of internal revolt and external war
Explanation: The Committee of Public Safety became powerful during the most dangerous phase of the French Revolution, when France faced serious internal and external threats. Revolutionary France was fighting foreign monarchies, while rebellion, political conflict, food problems, and resistance existed within the country. In this emergency, the committee was given broad authority to defend the revolution, control war efforts, and deal with suspected enemies. Its power was especially associated with the Reign of Terror.
Choice B is correct because it names both major pressures: internal revolt and external war. Permanent peace and prosperity would not normally justify extraordinary emergency power, so A is the opposite of the historical situation. C is unrelated, and D concerns the Industrial Revolution rather than the French Revolution. The committee’s growing authority must therefore be understood in the context of crisis, fear, war, and revolutionary emergency, not ordinary peaceful government.