Option c is the correct answer. Rock Edict II and XIII of Ashoka's major rock edicts provide insights into the Sangam Kingdom. Edict II discusses dhamma's establishment and mentions the Chola, Pandya, and Satiyaputa regions, referred to as "Sangam," highlighting their cultural significance. Edict XIII records Ashoka's remorse for Kalinga war and dhamma's spread in the south, reaching Cholas, Pandyas, and Ceylon. These edicts offer valuable information about Ashoka's rule and his efforts to promote dhamma in diverse regions of his empire.