Option 1: This statement is correct. Raja Rammohan Roy`s efforts did indeed lead to the formation of the Brahmo Samaj in 1828. The Brahmo Samaj was a socio-religious reform movement that aimed to establish a monotheistic Hindu society, free from idol worship and other social evils.

Option 2: This statement is correct. Raja Rammohan Roy believed in the concept of universal theism and considered different religions as embodiments of this universal theism. He emphasized the unity of all religions and sought to promote a rational understanding of religion.

Option 3: This statement is correct. Raja Rammohan Roy`s Vedantic monism, which emphasized the philosophical oneness of all religions, was strengthened after 1815 due to his exposure to Christian Unitarianism. Roy`s interactions with Christian Unitarians in England influenced his ideas and further shaped his approach to religious reform.

Option 4: This statement is not correct. Raja Rammohan Roy`s focus was not exclusively on the problems and issues of the emerging middle class of India. He was a social reformer who tackled various issues such as sati, the caste system, women`s rights, and education reforms. His efforts aimed to bring about social and religious