The correct answer to the question is option 3 - Hieun-Tsang. The Kannauj assembly, organized by Harsha, was held in honor of Hieun-Tsang. Hieun-Tsang was a Chinese Buddhist monk and scholar who traveled to India during the reign of Harsha. He spent several years in India, studying Buddhist scriptures and documenting his observations. Harsha, being a great patron of Buddhism, organized the Kannauj assembly as a way to honor Hieun-Tsang and showcase his teachings and knowledge to a larger audience. This assembly was a significant event in the history of ancient India, as it brought together scholars, monks, and intellectuals from various parts of the country.