In a land called Mysteria, there lives a wizard. 在一片名为神秘之地的大陆上，住着一位巫师。
The wizard can transform items into an assortment of other items. The order of these items will always be the same.这位巫师可以把物品变成各种各样的其他物品。这些物品的排列顺序总是固定的。
For example: if a coin is transformed into a potion and a dragon, the potion will always be on the left of the dragon.例如：如果一枚硬币被转化成一瓶药水和一条龙，那么药水总是会在龙的左边。
The table below shows the two possible ways a wizard can transform a diamond and the two possible ways he can transform a coin:下表展示了巫师将钻石进行转化的两种可能方式以及将硬币进行转化的两种可能方式：
| Before 之前 | After 后 |
 |
 |
|
|
|
  |
|
|
These magical transformations can happen any number of times, in any order. That is, any diamond and any coin can be transformed at any time. In this way, a long line of magical things can be created from a single diamond or coin.这些神奇的变化可以以任意次数、任意顺序发生。也就是说，任何一颗钻石和任何一枚硬币都可以在任何时候进行变化。通过这种方式，从一颗钻石或一枚硬币出发，可以创造出一长串神奇的事物。
Question: 问题:
Starting with a single diamond, which line is not possible to obtain?从一颗钻石开始，哪一行是无法得到的？
A. 
B. 
C. 
D. 
Explanation 解释
The correct answer is: 正确答案是：
Suppose the magical transformations are numbered 1 through 4 as follows:假设这些神奇的变形按如下方式编号为 1 至 4：
| Number 数量 | Before 之前 | After 后 |
|---|---|---|
| 1 | |
|
| 2 | |
|
| 3 | |
|
| 4 | |
|
can be obtained by starting with a single wizard and applying transformations, 1, 4, 2 and 3 in that order.可以通过从一个巫师开始，并依次应用变换 1、4、2 和 3 来获得。
can be obtained by starting with a single wizard and applying transformations 2, 2, 3, 4, and 1 in that order.可以通过从一个巫师开始，并依次应用变换 2、2、3、4 和 1 来获得。
can be obtained by starting with the single wizard and applying transformations 2, 1, 3 and 3 in that order.可以通过从单个巫师开始，并依次应用变换 2、1、3 和 3 来获得。
One quick way to see that is not possible is to notice that the transformation rules always create a potion and a dragon at the same time. Therefore, the number of potions in Mysteria will always equal the number of dragons, which is not the case in this answer option.要快速看出这是不可能的，只需注意到转化规则总是同时生成一瓶药剂和一条龙。因此，神秘岛上的药剂数量总是等于龙的数量，而这在该选项中并非如此。
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