当一棵树有倒的趋势时，护林工人常常用两根木棒撑住这棵树，这是三角形的( )在实际

I think _____ very important for students to study by themselves in the school or at home.

A. it B. this C. that

运动性失语表现为 （）

A.口语理解正常，口语表达障碍

B.神经系统器质性疾病引起的发音不清，但用词正确

C.没有手部肌肉瘫痪，但不能书写，仍能抄写

D.发音正常，口语理解障碍

E.没有失明，但对视觉性符号的认识能力丧失

Read the argument and the instructions that follow it, and then make any notes that will help you plan your response. Write your response on a separate sheet of paper. If possible, type your essay on a word processor.
A spokesman for a dairy company issued the following statement:
Many consumers buy organic milk because they are concerned about the consequences of the widespread use of recombinant bovine growth hormone and antibiotics in the conventional dairy industry. These concerns, however, are unfounded. While bovine growth hormone has been shown to produce significant developmental effects in cattle, no study has ever shown that its presence in commercial milk has had any developmental effects on human consumers. Regarding antibiotics, while it has been argued that large-scale, preemptive use of antibiotics in cattle feed can interfere with the animals’ immune systems and can lead to the proliferation of antibiotic-resistant strains of bacteria, neither of these effects affect the quality of the milk produced by cattle that are fed antibiotics. Therefore, there is no reasonable justification for a consumer to pay $5 for a gallon of organic milk when a perfectly good gallon of conventional milk can be had for half the price.
Discuss how well reasoned you find this argument. In your discussion, be sure to analyze the line of reasoning and the use of evidence in the argument. For example, you may need to consider what questionable assumptions underlie the thinking and what alternative examples or counterexamples might weaken the conclusion. You can also discuss what sort of evidence would strengthen or refute the argument, what changes in the argument would make it more logically sound, and what, if anything, would help you better evaluate its conclusion.

子宫肌瘤最常见的声像图表现为（）。

A.子宫体积增大，外形不规则，宫区出现强光团

B.子宫体积增大，外形不规则，宫区出现不规则液性暗区

C.子宫大小正常，外形规整，宫区出现结节状回声

D.子宫体积增大，外形规整，宫区光点弥漫性分布不均匀

E.子宫体积增大，外形不规则，宫区出现团块状回声

“十年树木，百年树人”说明教育具有（）

A.创造性

B.广延性

C.长期性

D.示范性