1[单选题]

<p style="TEXT-JUSTIFY: inter-ideograph; TEXT-ALIGN: justify; TEXT-INDENT: 21pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: Calibri; FONT-SIZE: 10.5pt; tab-stops: 158.25pt 212.65pt 233.9pt 333.15pt 460.7pt"><span style="FONT-FAMILY: 宋体">设区域</span><img style="VERTICAL-ALIGN: middle" width="14" height="14" src="http://www.jxjypt.cn/Content/Scripts/ewebeditor10/uploadfile/exam/201302/20130226160321314001.gif"><span style="FONT-FAMILY: 宋体">是由圆</span><img style="VERTICAL-ALIGN: middle" width="132" height="23" src="http://www.jxjypt.cn/Content/Scripts/ewebeditor10/uploadfile/exam/201302/20130226160321381002.gif"><span style="FONT-FAMILY: 宋体">围成，则二重积分</span><img style="VERTICAL-ALIGN: middle" width="89" height="37" src="http://www.jxjypt.cn/Content/Scripts/ewebeditor10/uploadfile/exam/201302/20130226160321705003.gif"><span>&nbsp;</span><span style="FONT-FAMILY: 宋体">（&nbsp; </span><span style="FONT-FAMILY: 宋体">）</span></p>
<p style="TEXT-JUSTIFY: inter-ideograph; TEXT-ALIGN: justify; TEXT-INDENT: 21pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: Calibri; FONT-SIZE: 10.5pt; tab-stops: 158.25pt 212.65pt 233.9pt 333.15pt 460.7pt"><span>A</span><span style="FONT-FAMILY: 宋体">．</span><img style="VERTICAL-ALIGN: middle" width="127" height="37" src="http://www.jxjypt.cn/Content/Scripts/ewebeditor10/uploadfile/exam/201302/20130226160321095004.gif"><span><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span>B</span><span style="FONT-FAMILY: 宋体">．</span><img style="VERTICAL-ALIGN: middle" width="121" height="46" src="http://www.jxjypt.cn/Content/Scripts/ewebeditor10/uploadfile/exam/201302/20130226160321188005.gif"></p>
<p style="TEXT-JUSTIFY: inter-ideograph; TEXT-ALIGN: justify; TEXT-INDENT: 21pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: Calibri; FONT-SIZE: 10.5pt; tab-stops: 158.25pt 212.65pt 233.9pt 333.15pt 460.7pt"><span>C</span><span style="FONT-FAMILY: 宋体">．</span><img style="VERTICAL-ALIGN: middle" width="115" height="35" src="http://www.jxjypt.cn/Content/Scripts/ewebeditor10/uploadfile/exam/201302/20130226160321587006.gif"><span><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span>D</span><span style="FONT-FAMILY: 宋体">．</span><img style="VERTICAL-ALIGN: middle" width="127" height="46" src="http://www.jxjypt.cn/Content/Scripts/ewebeditor10/uploadfile/exam/201302/20130226160321386007.gif"></p>

A.A

B.B

C.C

D.D