Yellapragada Subbarao (1895–1948) was an Indian biochemist who did most of his research in the United States, at Harvard and later at Lederle Laboratories.

Statement (i) is true: with Cyrus Fiske he identified phosphocreatine and the role of ATP as the energy source of muscle, and his team later developed methotrexate, one of the first anticancer drugs.

Statement (ii) is false: he was born at Bhimavaram in the Godavari region of the Madras Presidency, in present-day Andhra Pradesh, not in Arunachal Pradesh.

Statement (iii) is false as worded: at Madras Medical College he received only the lesser LMS certificate instead of the MBBS degree after he displeased his surgery professor by wearing a khadi surgical gown in support of the national movement; it was not because of wearing a dhoti. So only statement (i) holds, and every choice containing (ii) or (iii) fails.

(i) only option is correct.