This question is testing COMPARISON structure. Whenever we're comparing two things, we want the grammatical structures to be as similar as possible (although they don't necessarily have to be identical).

Over 75 percent of the energy produced in France derives from nuclear power, while in Germany it is just over 33 percent.

We want to compare energy in France to energy in Germany, so we need to test how the comparison structures are set up.

A. while in Germany it is just over 33 percent
The pronoun "it" does not have a legitimate antecedent here. It could refer to "energy" or "nuclear power."

B. compared to Germany, which uses just over 33 percent
If the subject of the first clause is "energy," this answer choice implies that we're comparing "energy" to "Germany," which does not make sense.

C. whereas nuclear power accounts for just over 33 percent of the energy produced in Germany
Here, we have inverted the ordering of the clause, but it's clear that we're comparing Germany to France, and energy to energy. Correct.

D. whereas just over 33 percent of the energy comes from nuclear power in Germany
The structure of this clause is more similar to the first, but there are meaning ambiguities. If we had rearranged it to say "... energy in Germany comes from nuclear power." it would be correct. As written, though, it implies that 33% of the energy everywhere comes from nuclear power in Germany. Not that 33% of German energy comes from nuclear.

E. compared with the energy from nuclear power in Germany, where it is just over 33 percent
Again, "it" doesn't have a legitimate antecedent. We also don't want to compare the percentage of all power in France with just the nuclear power in Germany.

The answer is C.

A note: please always post your SOURCE and the correct answer when posting questions.

Hi nahid078,

This is a quirky SC; I imagine that many Test Takers would get this question wrong since most of the wrong answers are written in "conversational english" instead of grammatical english.

Here, we're dealing with a comparison, so we must compare LIKE things. In most Comparison prompts, Parallel structure is normally maintained, but sometimes there are minor deviations.

The first part of the sentence discusses "% of the energy produced in France", so we have to make sure that the second part of the sentence offers information about a "% of the energy produced in Germany."

The only answer that offers this information in this format is Answer C

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