Final answer:
Yang Jian, founder of the Sui dynasty, was an adherent of Buddhism, reflecting this tradition's prominence during his rule.
Step-by-step explanation:
Yang Jian, the founder of the Sui dynasty, was an adherent of the Buddhist religious tradition. Despite his mixed cultural heritage and exposure to Confucian teachings, his and his family's deep commitment to Buddhism played a key role in his personal life and rule. Emperor Yang Jian, also known as Wendi, not only practiced Buddhism but also took steps to promulgate the religion during his reign, which showed the prominence of Buddhist tradition in his time.