Analysis of test questions: Zhan Tianyou's famous words, especially "Make the country rich and strong without foreign aggression", warn us that the Chinese nation should be self-reliant and self-reliant, which embodies the core of the Chinese national spirit, and item D is correct; Unity emphasizes the sense of wholeness; Peace-loving emphasizes solving problems by peaceful means and actively creates a stable international and domestic environment; Hard-working and brave, focusing on thrift, A, B, C are not in line with the meaning of the question.