dieterc
Is it also correct to cross off answers A and E because the ,which and ,where are nonessential modifiers and therefore result in a comparison that makes no sense of you leave them out?
Posted from my mobile device(A) and (E) don't make sense with their modifiers either! (A) seems to be saying that nuclear power is itself 33% in Germany. That's illogical. Nuclear can account for a percent of total energy use, but it cannot itself be a percent. And (E) does the same thing. No need to worry about what happens when we take out modifiers.
Generally speaking, when it comes to stripping out nonessential modifiers, it's better to think in terms of whether the sentence falls apart
grammatically than to consider whether the meaning becomes incoherent. The problem is that if the modifier is itself described by another portion of the sentence, the construction might make no sense when you remove it, even if it's not technically an error.
Consider:
Tim loves his daughter, who is obsessed with her class pet, a hamster that juggles tiny bowling pins.
This sentence is fine as is. It has a main clause, followed by two modifiers. But watch what happens when we strip out the part in red:
Tim loves his daughter, a hamster that juggles tiny bowling pins.
Clearly, our new construction raises a lot of questions about Tim. The problem is that we actually had two nonessential modifiers and one happened to describe the other. So even though it's illogical without a nonessential modifier, it is't wrong either.
The takeaway: if you want to remove a long nonessential modifier to see if a sentence has a subject-verb disagreement, go for it. But when it comes to considering logic, evaluate the entire sentence first, as removing modifiers may create a problem that doesn't actually exist.
I hope that helps a bit!