The correct answer is option 'D', i.e., 4th Schedule of the Indian Constitution talks about the allocation of seats in Rajya Sabha.

The 4th Schedule of the Indian Constitution provides details about the allocation of seats in the Rajya Sabha, which is the Upper House of the Parliament. It contains the names of the states and union territories, along with the number of seats allocated to each.

Here is a detailed explanation of the 4th Schedule and its significance:

1. Allocation of Seats: The 4th Schedule specifies the number of seats allocated to each state and union territory in the Rajya Sabha. The allocation is based on various factors like population, area, and special provisions for certain states.

2. Representation of States: The schedule ensures that each state and union territory has representation in the Rajya Sabha, irrespective of its size or population. This helps in maintaining federalism and ensuring that the interests of all regions are represented at the national level.

3. Special Provisions: The 4th Schedule also includes special provisions for certain states. For example, states like Uttar Pradesh, Bihar, and Madhya Pradesh have a higher number of seats compared to other states due to their larger population. Similarly, smaller states like Goa and Sikkim have fewer seats.

4. Union Territories: The schedule also includes the representation of union territories in the Rajya Sabha. While most union territories do not have elected representatives, they are allocated a certain number of seats in the Rajya Sabha to ensure their participation in the legislative process.

5. Amendments: The allocation of seats in the Rajya Sabha can be amended through a constitutional amendment. This ensures that the representation can be adjusted based on changing demographics or political considerations.

The 4th Schedule plays a crucial role in ensuring the representation of states and union territories in the Rajya Sabha. It helps in maintaining the balance of power between different regions and provides a platform for the states to voice their concerns and contribute to the legislative process at the national level.