The object of the Butler Committee of 1927 was to

The Butler Committee, appointed in December 1927 under Sir Harcourt Butler, was asked to examine the relationship between the British Crown and the Indian States, including the doctrine of paramountcy. Its report of 1929 dealt with how the Crown's overriding authority over states related to their internal autonomy and to the Government of India. So D is correct.

• A is wrong: The division of powers between the Centre and the provinces was a question for the Government of India Act 1919 (dyarchy) and later constitutional enquiries like the Simon Commission, not Butler.
• B is wrong: The powers of the Secretary of State were a matter for constitutional reform legislation such as the 1919 and 1935 Acts, not this committee.
• C is wrong: Press control came through laws like the Vernacular Press Act 1878 and the Indian Press Act 1910. Butler had no such brief.

Core concept: paramountcy, the Crown's supremacy over princely states. It connects to the later debate on integrating the states into an Indian federation, a recurring Mains theme on centre-state relations and princely India.

Trap: candidates confuse it with the Simon Commission, also set up in 1927, and assign it constitutional-reform or centre-province functions.