Which script was specific to the northwest region of the subcontinent for inscriptions during the Mauryan period?

Kharosthi

Asokan inscriptions predominantly utilized the Prakrit language, while in the northwestern region of the subcontinent, Aramaic and Greek were commonly employed. The majority of Prakrit inscriptions were composed in the Brahmi script, but certain inscriptions in the northwest used the Kharosthi script instead. As for Afghanistan, inscriptions were scripted in both Aramaic and Greek.