How are the inscriptions dated?

Both 1 and 2 are correct

Inscriptions are writings that have been carved or engraved onto hard surfaces, including stone, metal, or pottery. Typically, they serve as records of the accomplishments, activities, or ideas of the individuals or groups who commissioned them. These inscriptions often highlight the achievements of kings or document donations made by both women and men to religious institutions. As virtually permanent records, some inscriptions are dated, while others are assigned dates based on palaeography, which involves analyzing the writing styles with considerable accuracy.

The earliest inscriptions were composed in Prakrit, a language commonly used by ordinary people. In addition to Prakrit, inscriptions and texts were written in other languages such as Pali, Tamil, and Sanskrit. Although these languages were employed for writing purposes, it is worth noting that people may have spoken other languages not necessarily used for written records.