在人的手背上常常看到的一条条“青筋”其实是（　　）

图中对动植物体内糖类、脂质的分类正确的是（  ）

阅读下面对话，并根据要求完成相应任务。从所给的A、B、C、D、E选项中，选择正确的小标题。
①I am 73 years old. I often watch TV in my free time. Of all the programs, I like the news best. Through the TV, I can learn what is happening in our country and in the world. At seven every evening, I always sit in front of the TV. ____   
②I am a grandma. I like Chinese traditional opera. From Monday to Thursday, I usually turn on the TV at half past seven. The programs from CCTV7 are my best.  ____   
③I am a basketball fan. I like playing basketball very much. But I am too busy. So I have to watch it on TV. Every night, I watch the match till midnight. I am crazy about it. ____   
④I am a housewife. I do the housework all day, I'd like to watch TV at night. I like to watch soap operas such as "Palace", "Meteoric Garden" and so on.  ____   
⑤I am the only son in the family. I am in Grade One. I like cartoons best. I often watch cartoons on TV after doing the homework. ____   
A.          
B.           
C.         
D.         
E.  

两根平行导线通电后，会出现如图（甲）所示的现象（图中箭头表示电流方向，实线、虚线分别表示导线通电前、后的位置）．由此可以推断：在图（乙）所示的电路中，当开关S闭合时，长度会____（选填“变长”或“变短”，不考虑摩擦力），你判断的依据是：____；若螺线管的右端是N极，则电源右端是____极。

若对任意的 $x>0$ ，不等式 $x^2-2\left(m^2+m+1\right)\text{ln}x\ge 1$ 恒成立，则 $m=$ ____．