The conclusion of the argument is: "Therefore, antitheft devices do not protect cars against thieves." Why? Because insurance industry statistics show that "Cars with alarms or other antitheft devices are more likely to be stolen or broken into than cars without such devices or alarms." This is a correlation that the author then uses to make a cause and effect argument.
The observed effect the author is trying to explain is "cars with alarms or other antitheft devices are more likely to be stolen or broken into than cars without such devices or alarms." His proposed cause? These antitheft devices do not work.
The flaw here is that the author is overlooking the alternate possible explanation that it may, in fact, be that cars with antitheft devices are the most sought after cars by thieves (possibly why they have antitheft devices in the first place - to deter this). So antitheft devices could still be doing a good job of protecting cars against thieves, but it's just that thieves really want those cars that happen to have antitheft devices. Another way to look at this is that the author is overgeneralizing from an unrepresentative sample (i.e. cars with alarms or antitheft devices) to make a conclusion about these antitheft devices in general.
Answer choice (E) does not have similar flawed reasoning. The conclusion is: "Hence a society that wishes to establish a free public university should first establish a free public library." Why? "Societies that support free public libraries are more likely to support free public universities than are societies without free public libraries." Answer choice (E)'s flaw is incorrectly assuming a causation from a correlation. Just because societies that support free public libraries are more likely to support free public libraries does not mean that supporting free public libraries causes a society to support free public universities. Furthermore, merely establishing a free public library doesn't mean there will be support for the public library. There's no evidence in the answer choice to support the contention that establishment of a public library is the same as support of a free public university. Therefore, the reasoning is not the same as the argument.
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