While it costs about the same to run nuclear plants as other types of power plants, it is the fixed costs that stem from building nuclear plants that makes it more expensive for them to generate electricity.

While it costs about the same to run nuclear plants as other types of power plants, it is the fixed costs that stem from building nuclear plants that makes it more expensive for them to generate electricity.

While the cost of running nuclear plants is about the same as for other types of power plants, the fixed costs that stem from building nuclear plants make the electricity they generate more expensive.

Even though it costs about the same to run nuclear plants as for other types of power plants, it is the fixed costs that stem from building nuclear plants that makes the electricity they generate more expensive.

It costs about the same to run nuclear plants as for other types of power plants, whereas the electricity they generate is more expensive, stemming from the fixed costs of building nuclear plants.

The cost of running nuclear plants is about the same as other types of power plants, but the electricity they generate is made more expensive because of the fixed costs stemming from building nuclear plants.

##### 考题讲解

A选项：本选项中第一个it是一个形式主语，指代身后的不定式短语to run nuclear plants，还原为正常语序则有：
to run nuclear plants costs about the same as other types of power plants.

Running  nuclear plants costs about the same as other types of power plants

the cost of running nuclear plants is about the same as the cost for other types of power plants.

B选项：Correct. 本选项在语法和逻辑上均是正确的。

C选项：to run nuclear plants 错误同(A)；makes错误同(A)。

D选项：
to run nuclear plants 错误同(A)；另外，本选项中stemming from the fixed costs of building nuclear plants是the electricity they generate is more expensive的伴随状语（根据状语就近修饰原则），所以stem的逻辑主语是the electricity，这是不正确的。在逻辑上，源自于建造核电站的固定成本的（stem from  the fixed costs of building nuclear plants ）应该是“电能更贵”这件事，而不是电能（the electricity）本身。

E选项：比较对象不对等。在逻辑上具有same关系的应该是“运营核电站的成本”和“运营其它类型电站的成本”，因此应该用The cost of running nuclear plants is about the same as that of other types of power plants。