James Prinsep was a British officer and scholar who played a significant role in the deciphering of inscriptions, particularly the Brahmi script. His work was pivotal for understanding the political history of ancient India. By deciphering the inscriptions, Prinsep was able to provide valuable insights into the political events and rulers of the time. Thus, both Assertion (A) and Reason (R) are correct, and Reason (R) is directly linked as the explanation for Assertion (A).