In Charaka's texts, Shirish Beej (the seed of the Shirish plant) is associated with the therapeutic procedure of Shirovirechana.
- Vamana is a therapeutic vomiting procedure.
- Virechana is a purgation procedure.
- Asthapana Basti refers to a type of enema used in Panchakarma therapy.
However, Shirovirechana is specifically associated with Shirish Beej in Charaka's teachings.
Thus, the correct answer is (2) Shirovirechana.