A、<p><span style=\""font-family: 微软雅黑, 'Microsoft YaHei';\"">1<\/span><br><\/p>
B、<p><span style=\""font-family: 微软雅黑, 'Microsoft YaHei';\"">0<\/span><br><\/p>
C、<p><span style=\""font-family: 微软雅黑, 'Microsoft YaHei';\"">-1<\/span><br><\/p>
D、<p><img class=\""kfformula\"" src=\""data:image\/png;base64,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\"" data-latex=\""-\\frac {1} {2}\""><\/p>