Passage Summary: Since we can build a very efficient car and we can build a very safe car, the author assumes we can definitely build one car that does both things at once.

Conclusion: It is possible to manufacture a single car that is both twice as fuel-efficient as a normal car and meets side-impact safety standards.

Reasoning: Evidence shows we can achieve high fuel efficiency in a car, and separate evidence shows we can meet safety standards in a car.

Analysis: This argument suffers from a compatibility flaw, assuming that because two things are possible individually, they must be possible together. In the real world, these two goals might conflict—for example, safety features might add weight that ruins fuel efficiency. Look for an answer choice that takes two separate possibilities and joins them into a single 'super-possibility' without proving they can actually coexist.