The correct answer is option 2, Article 352. Article 352 of the Indian Constitution deals with the declaration of a national emergency. It allows the President of India to declare an emergency in the country, specifically on the grounds of war or external aggression. When such a situation arises, the President can exercise emergency powers and take necessary measures to handle the crisis effectively. During a national emergency, the central government gains additional authority to suspend some fundamental rights guaranteed by the Constitution. This provision is aimed at ensuring the security and stability of the nation during times of war or external aggression. It is important to note that emergency provisions under Article 352 are temporary and must be reviewed and ratified by Parliament within six months to continue their effect.