Option 1: A single citizenship - This feature is not common to both the Indian Federation and the American Federation. In India, there is a concept of dual citizenship where individuals can hold both Indian and foreign citizenship, while in the United States, only American citizenship is recognized.

Option 2: Dual judiciary - This feature is not common to both federations. In India, there is a unified judiciary system with a Supreme Court at the top, while in the United States, there is a dual judiciary system with separate federal and state courts.

Option 3: Three Lists in the Constitution - This feature is specific to the Indian Federation. The Indian Constitution includes three lists: Union List, State List, and Concurrent List, which enumerate the subjects on which the central government, state governments, and both can make laws, respectively.

Option 4: A Federal Supreme Court to interpret the Constitution - This feature is common to both the Indian Federation and the American Federation. Both federations have a Federal Supreme Court that has the power to interpret the constitution and uphold its principles.

Therefore, option 4 is the correct answer because it is a feature that is shared by both federations.