Explanation:

• Keeladi excavation site is a Sangam period settlement that is being excavated by the Archaeological Survey of India and the Tamil Nadu Archaeology Department. The settlement lies on the bank of the Vaigai River. This is a large-scale excavation carried out in Tamil Nadu after the Adichanallur archaeological site.

• In the fourth phase of excavations at Keezhadi, 72 potsherds with Tamil-Brahmi script were discovered at the site. Some of these artifacts have inscribed graffiti marks, similar to graffiti marks which some believe to have evolved from the Indus script.

Hence only statement 2nd is correct.