The question asks about the individual who first deciphered the Brahmi and Kharosthi scripts that were used in Ashoka's inscriptions. Let's evaluate the given options:
Based on the evaluations above, James Princep is the correct answer, as he was the first to decipher both the Brahmi and Kharosthi scripts. This work significantly contributed to understanding Indian history, specifically regarding the Mauryan period and the rule of Emperor Ashoka.
Conclusion: The correct answer is James Princep.