X、Y、Z为三种金属．X、Y放入稀硫酸中均放出氢气，Z与稀硫酸不反应，将X放入Y（NO₃）₂溶液中，有Y单质析出．X、Y、Z的活动性由强到弱的顺序是（   ）

阅读材料，回答问题。

材料一  他用不断的战争来代替不断的革命。

材料二  对德国来说，拿破仑并不像他的敌人所说的那样是一个专横跋扈的暴君。他在德国是革命的代表，是革命原理的传播者，是旧的封建社会的摧毁人。

材料三  他把他的法典带到被他征服的国家里，这个法典比历来的法典都优越得多。

看图，读一读，将字母序号写在横线上。

A. I like this plant. It's short. It has small leaves. It has three red flowers.

B. This is my plant. It's small. It has two small leaves. I water it every day.

C. There are two seeds. They are under the ground. They drink the rain water.

D. I have a new plant. It's green. It has long leaves. It has small flowers too.