根据短文理解，从A、B、C、D四个选项中选择最佳一项填空。

    Learning how to play the piano is not the only way for children to have a bright future. Children can choose what they like in many ways. Many children are good at sports. Maybe they will be great players when they grow up.

    Here is another example: the 1 in Shanghai have paid much attention to story-telling. Story-telling can also make them 2 excellent students. They 3 many story-telling contests every year. And children have 4 great interest and taken an active part in them. Some students who were too shy to speak in public have been now very good 5. 

    Now many parents 6 their children to learn how to play the piano or the violin. 7 the money and energy they spend cannot make sure that their children will 8 much in a short period of time. However, training children to tell a story is quite9.Although it costs little, it's a good and an easy way 10 children to develop.

学习了Ca（OH）₂的性质后，小科编了一首《新石灰吟》：“千锤万凿出深山（开采：石灰石），烈火焚烧却是生（CaCO₃CaO+CＯ₂↑）．用水一泼就熟了〔CaO+H₂O=Ca（OH）₂〕，留下洁白在人间〔Ca（OH）₂+CO₂═CaCO₃↓+H₂Ｏ〕”下列对这首诗所描述的化学知识的说法中，错误的是（　　）

如图所示，面积为0.02m²、内阻不计的100匝矩形线圈ABCD，绕垂直于磁场的轴OO′匀速转动，转动的角速度为100rad/s，匀强磁场的磁感应强度为 $\frac{\sqrt{2}}{2}$ T．矩形线圈通过滑环与理想变压器相连，触头P可移动，副线圈所接电阻R=50Ω，电表均为理想交流电表．当线圈平面与磁场方向平行时开始计时．下列说法正确的是（　　）

17世纪至19世纪，欧美主要资本主义国家都通过革命战争或和平改革制定了宪法，设立了议会，确立了资产阶级代议制度。近代西方资产阶级代议制度的突出特征是