The correct answer is option 1: Four. The Fundamental Duties were added to the Indian Constitution as Part IV-A by the 42nd Amendment Act in 1976. They were introduced to promote a sense of responsibility and patriotism among Indian citizens. The four fundamental duties were included under Article 51A of the Constitution. These duties include respecting the national flag and the national anthem, promoting harmony and the spirit of common brotherhood, preserving the rich heritage of the nation, and protecting and improving the natural environment. It is important for citizens to understand and fulfill these duties in order to contribute to the overall development and progress of the country.