D

Test question analysis: This question tests knowledge points such as the principle of the unity of contradictions and opposites and the infinity of knowledge. The question stem says that the more you know, the more knowledge you have. The bigger the circle is, the more you don’t know, which shows that the contradictory parties are unified, and also shows that knowledge is infinite. Therefore, ①③ is consistent with the meaning of the question, and ②④ is correct but inconsistent with the meaning of the question, so the answer should be D .