Although the Union List, State List and Concurrent List together cover almost the entire field of legislation, which authority has the power to make laws on a subject not mentioned in any of these lists under the Constitution of India?

Introduction / Context:
The Constitution of India distributes legislative powers between the Union and the States through the Union List, State List and Concurrent List in the Seventh Schedule. However, it is practically impossible to foresee every new subject or activity that may arise in the future. For this reason, the Constitution also provides for residuary powers, that is, authority to legislate on matters not mentioned in any of the three lists. This question examines your understanding of which body in India holds this residuary legislative power.

Given Data / Assumptions:
- India follows a federal system with a clear division of legislative subjects.
- Union List, State List and Concurrent List specify most topics of legislation.
- The question focuses on subjects not mentioned anywhere in these lists, called residuary subjects.
- The options mention Parliament, State Legislatures, both, neither and the Supreme Court as possible holders of this residuary power.

Concept / Approach:
Article 248 of the Constitution of India and Entry 97 of the Union List are crucial. They clearly state that Parliament has exclusive power to make laws with respect to any matter not enumerated in the Concurrent List or State List. These are called residuary subjects. Unlike some other federations where residuary powers lie with the states, in India they were consciously given to the Union to maintain unity and respond quickly to new national level issues such as information technology, cyber laws and space research.

Step-by-Step Solution:
Step 1: Recall that Article 248 and Entry 97 of the Union List deal with residuary powers of legislation.Step 2: Note that these provisions confer exclusive power on Parliament to make laws on any subject not mentioned in the State List or Concurrent List.Step 3: Understand that State Legislatures can only legislate on State List subjects and Concurrent List subjects shared with Parliament.Step 4: Recognise that courts, including the Supreme Court, interpret the Constitution but do not hold general legislative power over new subjects.Step 5: Conclude that Parliament of India alone holds the residuary legislative power, making option A correct.

Verification / Alternative check:
An alternative way to verify is to recall examples of new topics which were not originally foreseen, such as cyber crime, aspects of telecommunications or biotechnology. Parliament has enacted national laws on these subjects because they fall under residuary powers. Standard polity resources also state that unlike federations like the United States, where residuary powers usually rest with the states, in India they deliberately lie with the Union Parliament. This comparative perspective confirms the choice of option A.

Why Other Options Are Wrong:
State Legislatures do not have residuary powers and cannot legislate on subjects absent from the lists, so option B is incorrect. Option C is wrong because there is no joint residuary power for both Parliament and State Legislatures. Option D is incorrect since the Constitution clearly assigns residuary powers to Parliament rather than leaving a vacuum. Option E is wrong because the Supreme Court interprets laws and reviews their constitutional validity but does not legislate on unspecified subjects in a general sense.

Common Pitfalls:
Many learners wrongly assume that residuary powers must belong to the states because India is described as a federal country. Others confuse judicial review, which is a power of the Supreme Court, with legislative power. Another frequent mistake is forgetting the specific language of Article 248 and Entry 97, leading to wrong guesses in multi option questions. Careful revision of how legislative powers are distributed can help avoid these errors.

Final Answer:
Parliament of India only enjoys the residuary power to legislate on subjects not mentioned in any of the three lists under the Constitution of India.