The correct answer is: A. at all times.
The Parliament of India has the power to make laws on any subject not
enumerated in the Concurrent List or the State List. These are called residuary powers. The Parliament can make use of these powers at all times, even during a national emergency.The Concurrent List is a list of subjects on which both the Parliament and the State Legislatures can make laws. The State List is a list of subjects on which only the State Legislatures can make laws. The residuary powers are the powers to make laws on any subject not enumerated in the Concurrent List or the State List.
The Parliament can make use of the residuary powers to make laws on any subject, including those that are not mentioned in the Constitution. For example, the Parliament has made laws on subjects such as education, health, and environment, even though these subjects are not mentioned in the Constitution.
The Parliament can also make use of the residuary powers to amend the Constitution. For example, the Parliament has amended the Constitution to provide for a new All India Judicial Service and to create a National Judicial Appointments Commission.
The Parliament’s power to make use of the residuary powers is a very important power. It allows the Parliament to make laws on any subject that is not mentioned in the Constitution, and it also allows the Parliament to amend the Constitution. This power is essential for the Parliament to be able to function effectively and to meet the needs of the people of
India.Option B is incorrect because the Parliament can make use of the residuary powers at all times, not only during a national emergency.
Option C is incorrect because the Parliament can make use of the residuary powers on any subject, not only on subjects that are related to national emergency or constitutional emergency.
Option D is incorrect because the Parliament can make use of the residuary powers at all times.