Explanation: Sikkim, a state in northeastern India, has a unique history that sets it apart from other Indian states. Originally an independent kingdom, Sikkim was ruled by a monarchy until 1975. In that year, a referendum was held, and the people of Sikkim voted unanimously to become a part of India. This unanimous decision was a significant political event, as it marked the end of Sikkim's status as an independent kingdom and its integration into the Indian Union as a state.
The name "Sikkim" itself has remained unchanged since the state's integration into India. This is noteworthy because many other states in India have undergone name changes or have been formed from existing regions. For example, Uttarakhand was formed in 2000 from the northern districts of Uttar Pradesh, and the name "Uttarakhand" was chosen to reflect the region's geographical and cultural identity. Similarly, Tamil Nadu has been a state since the formation of India and has not undergone a name change.
Sikkim's unanimous approval to become a part of India is a testament to the political and social changes that occurred in the region. The integration of Sikkim into India was a peaceful process, and the name "Sikkim" has remained a symbol of the state's unique identity within the Indian Union. This historical context is crucial for understanding the significance of Sikkim's name and its place in the broader context of Indian geography and politics.
In summary, Sikkim is the correct answer because it is the only state among the options that was unanimously approved to become a part of India, and its name has remained unchanged since its integration. This makes Sikkim a unique case in the history of Indian states and their political evolution.