Which of the following statements is/are true?
(I) The 'Drain Theory' was put forth by Gopalkrishna Gokhale.
(II) The theory stated that the British exploited India for resources, and India received minimum or no returns.
(III) It also claimed that Britishers who worked in India sent most of their savings to England.
(IV) The interest paid by the British on the loans taken to develop the railways was the main basis of Indian income.