A、<strong><span style="font-size:14px;font-family:宋体">曲线单调减少</span></strong>

B、<strong><span style="font-size:14px;font-family:宋体">曲线单调增加</span></strong>

C、<strong><span style="font-size:14px;font-family:宋体">曲线既不增、也不减</span></strong>

D、<strong><span style="font-size:14px;font-family:宋体">曲线图形上凹</span><span style="font-size: 14px;font-family:&#39;Times New Roman&#39;,&#39;serif&#39;">(</span><span style="font-size:14px;font-family:宋体">凹弧</span><span style="font-size:14px;font-family:&#39;Times New Roman&#39;,&#39;serif&#39;">)</span></strong>

E、<strong><span style="font-size:14px;font-family:宋体">曲线图形下凹（凸弧</span><span style="font-size:14px;font-family:&#39;Times New Roman&#39;,&#39;serif&#39;">)&nbsp;</span></strong>