By the seventh century there were big landlords or warrior chiefs in different regions of the subcontinent. Existing kings often acknowledged them as their subordinates or samantas.
They were expected to bring gifts for their kings or overlords, be present at their courts and provide them with military support.
As samantas gained power and wealth, they declared themselves to be maha-samanta, mahamandaleshvara (the great lord of a “circle” or region) and so on.
Sometimes they asserted their independence from their overlords.

Both statements are correct.
The Battle of Plassey was essentially due to the conflicts between the Bengal Nawab and the East India Company. This is judged to be one of the pivotal battles in the control of Indian subcontinent by the colonial powers.
The British now wielded enormous influence over the Nawab and consequently acquired significant concessions for previous losses and revenue from trade.
The British further used this revenue to increase their military might and push the other European colonial powers such as the Dutch and the French out of South Asia, thus expanding the British Empire.

1 and 3 are incorrect.

The Theosophical Society was founded in New York (USA) in 1875 by Madam H.P. Blavatsky, a Russian lady, and Henry Steel Olcott, an American colonel.
Their main objectives were to form a universal brotherhood of man without any distinction of race, colour or creed and to promote the study of ancient religions and philosophies. They arrived in India and established their headquarters at Adyar in Madras in 1882.
Later in 1893, Mrs. Annie Besant arrived in India and took over the leadership of the Society after the death of Olcott. Mrs. Annie Besant founded the Central Hindu School along with Madan Mohan Malaviya at Benaras which later developed into the Banaras Hindu University.

Option d is correct.

Asoka was the first ruler who inscribed his messages to his subjects and officials on stone surfaces – natural rocks as well as polished pillars.
He used the inscriptions to proclaim what he understood to be dhamma. This included respect towards elders, generosity towards Brahmanas and those who renounced worldly life, treating slaves and servants kindly, and respect for religions and traditions other than one’s own.