单项选择题
A.stringB.boolC.PCDATAD.doucument
A.Dynamic Type DefinitionB.Do The DanceC.Document Type DefinitionD.Direct Type Definition
A.‹xml version="1.0"encoding="UTF-8"›B.‹?XML version="1.0"encoding="UTF-8"?›C.‹?xml Version="1.0"encoding="UTF-8"?›D.‹?xml version="1.0"encoding="UTF-8"?›