✅ Answer: B) Parliament (Centre)Residuary powers (subjects not in any list) vest with Parliament under Article 248. This is a unitary feature — in the USA, residuary powers are with the States. The concept of residuary powers with the Centre was borrowed from Canada.

✅ Answer: C) Article 280The Finance Commission is constituted under Article 280. It is constituted by the President every 5 years. It recommends the distribution of taxes between Centre and States and grants-in-aid to States.

✅ Answer: A) Article 249Article 249 allows Parliament to legislate on State List subjects when Rajya Sabha passes a resolution by 2/3 majority declaring it necessary in national interest. This is valid for 1 year (extendable). Article 250 applies during National Emergency, Article 252 when States request, and Article 253 for international agreements.

✅ Answer: B) It held that federalism is basic structure and President’s Rule is subject to judicial reviewThe S.R. Bommai case (1994) is the most important case on Centre-State relations. The SC held that federalism and secularism are basic structure elements, and the imposition of President’s Rule under Article 356 is subject to judicial review.

✅ Answer: C) 101st AmendmentThe GST Council was established by the 101st Constitutional Amendment (2016) under Article 279A. It is chaired by the Union Finance Minister. Decisions are taken by 3/4 majority — Centre has 1/3 vote and States together have 2/3 vote.

✅ Answer: C) Article 263The Inter-State Council is established under Article 263. It was established in 1990 on the recommendation of the Sarkaria Commission. It is chaired by the Prime Minister and includes Chief Ministers of all States and UTs with legislatures.

✅ Answer: C) AustraliaThe Concurrent List was borrowed from the Australian Constitution. Australia also has a similar system where both the federal government and states can legislate on concurrent subjects. In case of conflict, the federal law prevails.

✅ Answer: B) Centre-State relationsThe Sarkaria Commission (1983-88) was appointed to review Centre-State relations. It recommended the establishment of the Inter-State Council (established in 1990), greater autonomy to States, and restraint in using Article 356 (President’s Rule).

✅ Answer: B) Union Home MinisterZonal Councils are chaired by the Union Home Minister. They are statutory bodies (not constitutional) established under the States Reorganisation Act, 1956. India is divided into 5 zones. The Inter-State Council is chaired by the Prime Minister.

✅ Answer: A) Union law prevails (Article 254)Under Article 254, in case of conflict between a Union law and a State law on a Concurrent List subject, the Union law prevails. However, if the State law was reserved for the President’s assent and received it, the State law prevails in that State.