Passage Two 
51. 正确选项 C。Scholars and policymakers have different opinions about it. 
52. 正确选项A。Pre-K achievements usually do not last long. 
53. 正确选项B。When it is made part of kids’education. 
54. 正确选项D。She is a firm supporter of pre-K 
55. 正确选项C。Early intervention.