Which one of the following is not a characteristic feature of Indian

Which one of the following is not a characteristic feature of Indian Federalism ?

The federating units consented to form a union
Residuary powers vest with the Centre
Single citizenship
An extensive Union and Concurrent list
This question was previously asked in
UPSC CDS-1 – 2022
Option A is correct because, unlike federations like the USA, the Indian union was not formed by an agreement or consent among already existing independent states (federating units). The states were formed by carving out territories from British India and integrating princely states. This makes the Indian union “indestructible” while the states are “destructible” (their boundaries can be altered by Parliament).
Indian federalism is often described as quasi-federal or federal in form but unitary in spirit, with a strong central government. One key difference from classical federations is the origin of the union.
Characteristic features of Indian federalism include the division of powers between Centre and States (albeit with a strong Centre), a written constitution, the supremacy of the constitution, an independent judiciary, residuary powers with the Centre (B), single citizenship (C), and a detailed distribution of legislative subjects through extensive lists (D). The non-consensual formation of the union is a key aspect that distinguishes Indian federalism.