要求设计一个电磁限流器，当电路中电流过大时，它能切断电路，并需手动闭合。兴趣小组设计了两个电磁限流器，示意图如下，其中的C、D为动触点。下列说法中正确的是（　　）

A

When I drove to work yesterday, I met a traffic jam（交通阻塞）.As I looked out of my window, a young man was walking on the street. He was walking to the bridge. There were some homeless men with their cups around there. The young man went to one of them. He brought out some money, said a few words to him and put the money into his cup. He continued（继续）to walk and then saw another homeless man. He stopped for a minute, said a few words and then gave the man a candy.

And then he saw the next homeless man. He was shivering（冷得发抖）because of coldness. The young man now stopped and gave his scarf to him. He then said goodbye to him with a big smile and went away in the snow.

At that moment, I was in tears（流泪）.I gave this young man my best wishes with love and blessings.

下列句子从句式角度看，与所给例句相同的一项是（    ）
例句：为仲卿母所遣，自誓不嫁

用代入法解方程组$\left\{\begin{array}{c}7x-2y=3\left(1\right)\\ x-2y=-12\left(2\right)\end{array}\right.$有以下步骤：

①：由（1），得y=$\frac{7x-3}{2}$（3）；

②：由（3）代入（1），得7x-2×$\frac{7x-3}{2}$=3；

③：整理得3=3；
④：∴x可取一切有理数，原方程组有无数个解
以上解法，造成错误的一步是（　　）