在 XHTML 中有哪些不同的 DTD ？

<span style、"font-family: Calibri; font-size: small;"> Strict, Transitional, Frameset</span>

<span style、"font-family: Calibri; font-size: small;">Strict, Transitional, Loose, Frameset</span>

<span style、"font-family: Calibri; font-size: small;">Strict, Transitional, Loose</span>