Option b is the correct answer. The inscriptions of Ashoka, the Mauryan emperor known for spreading Buddhism and his rock edicts, were primarily written in Prakrit language. Prakrit was a group of ancient Indian languages that developed from Sanskrit and was commonly spoken by the people of that time. It was a more accessible and understandable language for the general population compared to Sanskrit, which was often used for more formal and scholarly purposes. The use of Prakrit in Ashoka's edicts helped in effectively communicating his messages about moral and ethical principles to a wider audience across his empire.