Read the passage and answer the questions that follow:
War was declared in April 1792. Defeat, which the people (plausibly enough) ascribed to royal sabotage and treason, brought radicalization. In August-September the monarchy was overthrown, the Republic one and indivisible established, a new age in human history proclaimed with the institution of the Year I of the revolutionary calendar, by the armed action of the Sansculotte masses of Paris. The iron and heroic age of the French Revolution began among the massacres of the political prisoners, the elections to the National Convention—probably the most remarkable assembly in the history of parliamentarism—and the call for total resistance to the invaders. The king was imprisoned, the foreign invasion halted by an undramatic artillery duel at Valmy.
Revolutionary wars impose their own logic. The dominant party in the new Convention were the Girondins, bellicose abroad and moderate at home, a body of parliamentary orators of charm and brilliance representing big business, the provincial bourgeoisie and much intellectual distinction. Their policy was utterly impossible. For only states waging limited campaigns with established regular forces could hope to keep war and domestic affairs in watertight compartments, as the ladies and gentlemen in Jane Austen's novels were just then doing in Britain. The Revolution waged neither a limited campaign nor had it established forces: for its war oscillated between the maximum victory of world revolution and the maximum defeat which meant total counter-revolution, and its army—what was left of the old French army—was ineffective and unreliable. Dumouriez, the Republic's leading general, was shortly to desert to the enemy.
The answer to the above question can be found in the line: The king was imprisoned, the foreign invasion halted by an undramatic artillery duel at Valmy.
Therefore, option 1 is the correct answer.