A city council member argues: "Since installing speed cameras, accidents at major intersections have decreased by 30%. Speed cameras clearly save lives." Which of the following, if true, most weakens the argument?

The correct answer to the question "A city council member argues: "Since installing speed cameras, accidents at major intersections have decreased by 30%. Speed cameras clearly save lives." Which of the following, if true, most weakens the argument?" is Option B: During the same period, the city also redesigned the intersections with better signage.

The other options — A) Speed cameras generate revenue for the city, C) Some drivers slow down near cameras but speed up elsewhere, D) Other cities have seen similar results — are incorrect for this General Knowledge question. As explained above: The argument attributes the accident decrease solely to speed cameras. If the city also redesigned intersections, there is an alternative cause for the decrease, weakening the causal claim.