C

Test question analysis: "The simplest thing is persistence, and the most difficult thing is persistence" emphasizes that persistence is required for both simplicity and difficulty, that is, The universality of contradiction; "If you regard the people around you as angels, you will live in heaven" emphasizes that we should treat the world with an optimistic attitude, that is, ① consciousness has active creativity and conscious selectivity; "Pride is the egg laid by victory" , but what hatches is failure" reflects the mutual transformation of the two contradictory parties under certain conditions; "Language is a beautiful flower, only action can achieve real results" emphasizes the importance of practice, that is, practice is the purpose and destination of knowledge.