Tina started with one circle and one square: 蒂娜从一个圆和一个正方形开始：
Then she created this heart from these shapes:然后她用这些形状拼出了这颗心：
Tina only used these kinds of operations on the shapes:蒂娜仅对这些图形使用了以下这些操作：
- Rotate: Rotate the shape by any amount in either direction.旋转：可将图形沿任意方向旋转任意角度。
- Move: Move the shape anywhere.操作：将图形移动到任何位置。
- Duplicate: Create a copy of the shape in the same location.复制：在相同位置创建形状的副本。
Question:问题:
Which of the following sequence of operations could Tina have used?以下哪一系列操作是蒂娜可能用过的？
A. Duplicate circle. Rotate square. Move circle. Move circle.复制圆。旋转正方形。移动圆。移动圆。
B. Duplicate square. Rotate square. Move square. Move circle.复制正方形。旋转正方形。移动正方形。移动圆形。
C. Duplicate circle. Rotate circle. Move circle. Move square.复制圆。旋转圆。移动圆。移动正方形。
D. Move circle. Move circle. Duplicate circle. Move square.移动圆。移动圆。复制圆。移动正方形。
Explanation 解释
Answer: 答:
A. Duplicate circle. Rotate square. Move circle. Move circle.复制圆。旋转正方形。移动圆。移动圆。
The square needs to be rotated so that one corner is facing down. This only happens in sequences "Duplicate circle. Rotate square. Move circle. Move circle." and "Duplicate square. Rotate square. Move square. Move circle.". Next, you can see that you need two circles to create a heart.正方形需要旋转，使一个角朝下。这种情况只会在“复制圆。旋转正方形。移动圆。移动圆。”和“复制正方形。旋转正方形。移动正方形。移动圆。”这两个序列中出现。接下来，您可以看到需要两个圆才能组成一个心形。
Sequence "Duplicate square. Rotate square. Move square. Move circle." cannot be correct because it does not create a second circle. This leaves the first one: "Duplicate circle. Rotate square. Move circle. Move circle." as the only correct sequence. The images below show the shapes (made see-through) after each of the first three operations of this sequence. After the final fourth operation, the heart is created. This verifies that Tina could have used sequence "Duplicate circle. Rotate square. Move circle. Move circle."序列“复制正方形。旋转正方形。移动正方形。移动圆形。”不可能正确，因为它没有生成第二个圆形。这使得第一个序列：“复制圆形。旋转正方形。移动圆形。移动圆形。”成为唯一正确的序列。下面的图片展示了此序列前三个操作后图形（已设置为透明）的样子。在最后的第四个操作之后，心形就形成了。这证实了蒂娜可能使用了序列“复制圆形。旋转正方形。移动圆形。移动圆形。”
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