Analysis of test questions: The truth in the material refers to "life is indifferent and simple, the state of mind is peaceful and quiet, not tempted by external material desires, and there is no emotional disturbance in the heart, and I am selfless". The title 1 is wrong, because the development of things is not periodic; Topic 4 is wrong, because the development of physical objects is its own negation, not the negation of external forces, so it is excluded; The answer is C.