The correct answer is option 3, Article 51A. This article of the Constitution of India deals with fundamental duties. Fundamental duties are a set of moral obligations that every citizen of India is expected to fulfill. These duties were added to the Constitution by the 42nd Amendment Act in 1976. The fundamental duties serve as a reminder to every citizen to contribute positively to society and the nation as a whole. Some of the fundamental duties listed in Article 51A include respecting the Constitution, upholding the unity of the country, promoting harmony, cherishing and preserving the rich heritage of India, protecting the natural environment, and striving towards excellence in all spheres of individual and collective activity. These duties are considered important for maintaining the integrity and progress of the nation.