The correct responses that describe how Legalism helped Shi Huangdi centralize Qin power are:
- It emphasized that the strength of a ruler rather than his goodness was most important.
- It asserted that people are greedy, and only tough laws and punishments can maintain order.
These principles of Legalism aligned with Shi Huangdi's approach to governance, allowing him to consolidate power through strict laws and centralized control.