Raja Ram Mohan Roy attacked which one of the following?

The correct answer is Option (2) → practice of Sati and ban on widow remarriage

Option (2) practice of Sati and ban on widow remarriage — Correct. The social reform movements of the nineteenth century took up the well-known social evils of sati, child marriage, ban on widow remarriage and caste discrimination. Raja Ram Mohun Roy attacked the practice of sati, appealing both to humanitarian and natural rights doctrines and to the Hindu shastras.