Explanation:

• Vidyasagar’s contribution to the making of modern India is many-sided. He evolved a new technique of teaching Sanskrit. He wrote a Bengali primer which is used till this day. By his writings, he helped in the evolution of a modern prose style in Bengali.
• He opened the gates of the Sanskrit college to non-Brahmin students for he was opposed to the monopoly of Sanskrit studies that the priestly caste was enjoying at the time. To free Sanskrit studies from the harmful effects of self-imposed isolation, he introduced the study, of Western thought in the Sanskrit College. He also helped found a college which is now named after him.
• Above all Vidyasagar is remembered gratefully by his countrymen for his contribution to the uplift of India’s down-trodden womanhood. He waged a long struggle in favour of widow remarriage. His humanism was aroused to the full by the sufferings of the Hindu widows. To improve their lot he gave his all and virtually ruined himself. He raised his powerful voice, backed by the weight of immense traditional learning, in favour of widow remarriage in 1855. Soon a powerful movement in favour of widow remarriages was started which continues till this day. Later in the year 1855, a large number of petitions from Bengal, Madras, Bombay, Nagpur were presented to the Government asking it to pass an act legalising the remarriage of widows (The Hindu Widows' Remarriage Act, 1856.). This agitation was successful and such a law was enacted. The first lawful Hindu widow remarriage among the upper castes in our country was celebrated in Calcutta on 7 December 1856 under the inspiration and supervision of Vidyasagar. Widows of many other castes in different parts of the country already enjoyed this right under customary law.
• Hence, all the given statements are correct.