单选 HTML5 的正确 doctype 是( )

A、<!DOCTYPEhtml>

B、<!DOCTYPEHTML5>

C、<!DOCTYPEHTMLPUBLIC"-//W3C//DTDHTML5.0//EN""http://www.w3.org/TR/html5/strict.dtd">

D、<!DOCTYPEhtmlPUBLIC"-//W3C//DTDXHTML1.0Transitional//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">