【单选题】
函数<img src=https://huaweicloudobs.ahjxjy.cn/0D30A78C08779470F014F8981A51DEB5.png title=VDT[$6{$YPCOC5TFU@P7S1D.png alt=VDT[$6{$YPCOC5TFU@P7S1D.png/>的单调减区间是( )
①
<img src=https://huaweicloudobs.ahjxjy.cn/6F0F83B279A0A15D16A0DEB559E7895E.png title=`{HG0)G06HAAMFLFA%(RCAA.png alt=`{HG0)G06HAAMFLFA%(RCAA.png/>
②
<img src=https://huaweicloudobs.ahjxjy.cn/AD64374B4CAF88222BF94108D2CAA08A.png title=1]D(_AA80_B[4XP2VITH8B8.png alt=1]D(_AA80_B[4XP2VITH8B8.png/>
③
<img src=https://huaweicloudobs.ahjxjy.cn/4BDD3F095367274C266579FAACA7DF5F.png title=9@BZWKCCWBDSGRPM6{Y3CEE.png alt=9@BZWKCCWBDSGRPM6{Y3CEE.png/>
④
<img src=https://huaweicloudobs.ahjxjy.cn/866D82A73978B2995072963CDD64F287.png title=TO`CVU({[~KL`~7W(G2EOVX.png alt=TO`CVU({[~KL`~7W(G2EOVX.png/>