Which one among the following was not a proposal of the Cabinet Mission, 1946?

The Cabinet Mission Plan of 1946 proposed a framework for India's independence and the formation of a Constituent Assembly. It suggested that the Assembly be constituted on the democratic principle of population strength, allotting seats to provinces and states in a ratio of roughly 1:1,000,000 [2]. The plan provided for an Indian Union comprising both British Indian Provinces and Princely States. Crucially, the Mission intended for the Assembly to frame a constitution for Indians, by Indians, without British supervision [2]. While the British Government intervened later to clarify grouping clauses and stated they would not force a constitution on unwilling parts of the country, they did not propose to supervise the Assembly's internal affairs. Instead, the Assembly was to be a sovereign body for the purpose of drafting the constitution, eventually concluding a treaty with Britain regarding the transfer of power [2].

Sources

1. [2] https://en.wikipedia.org/wiki/1946_Cabinet_Mission_to_India