Which of the following is/are the principal feature(s) of the Government of India Act, 1919?<br/>1. Introduction of diarchy in the executive government of the provinces.<br/>2. Introduction of separate communal electorates for Muslims.<br/>3. Devolution of legislative authority by the centre to the provinces.<br/><br/>Select the correct answer using the codes given below:

1. Introduction of diarchy in the executive government of the provinces — Correct. The Government of India Act, 1919 introduced diarchy in provinces, dividing subjects into transferred and reserved.

2. Introduction of separate communal electorates for Muslims — Incorrect. Separate electorates for Muslims were introduced earlier by the Indian Councils Act, 1909 (Morley-Minto Reforms), not first by the 1919 Act.

3. Devolution of legislative authority by the centre to the provinces — Correct. The 1919 Act expanded provincial legislative powers and marked a step toward decentralization.

Hence, 1 and 3 only are correct.