Evidence has been found through years of study______ children\'s early sleeping problem is likely to continue when they grow up. 

A、<span lang="EN-US" style="font-size:12.0pt;font-family: &quot;Times New Roman&quot;,serif;mso-fareast-font-family:宋体;mso-font-kerning:1.0pt; mso-ansi-language:EN-US;mso-fareast-language:ZH-CN;mso-bidi-language:AR-SA">why</span>

B、<span lang="EN-US" style="font-size:12.0pt;font-family: &quot;Times New Roman&quot;,serif;mso-fareast-font-family:宋体;mso-font-kerning:1.0pt; mso-ansi-language:EN-US;mso-fareast-language:ZH-CN;mso-bidi-language:AR-SA">how</span>

C、<span lang="EN-US" style="font-size:12.0pt;font-family: &quot;Times New Roman&quot;,serif;mso-fareast-font-family:宋体;mso-font-kerning:1.0pt; mso-ansi-language:EN-US;mso-fareast-language:ZH-CN;mso-bidi-language:AR-SA">&nbsp;whether&nbsp;</span>

D、<span lang="EN-US" style="font-size:12.0pt;font-family: &quot;Times New Roman&quot;,serif;mso-fareast-font-family:宋体;mso-font-kerning:1.0pt; mso-ansi-language:EN-US;mso-fareast-language:ZH-CN;mso-bidi-language:AR-SA">that</span>