A、<p><span style="font-family: 微软雅黑, 'Microsoft YaHei';">高阶无穷小</span><br></p>
B、<p><span style="font-size:14px;font-family:'微软雅黑','sans-serif'">同阶无穷小，但不等价</span></p>
C、<p><span style="font-family: 微软雅黑, 'Microsoft YaHei';">低阶无穷小</span><br></p>
D、<p><span style="font-family: 微软雅黑, 'Microsoft YaHei';">等价无穷小</span><br></p>