Critical Reasoning (CR) | Critical Reasoning (Weaken)

19. The owner of a four-story commercial building discovered termites in the building's first and second floors and called an exterminator. The Exterminator pumped gas into the walls on both the first and second floors. Due to the exterminator's work, the termites on those floors were killed quickly.

Which of the following, if true, most seriously undermines the validity of the explanation for the speed with which the termites were killed?

a. The third floor had no termite infestation.
b. Even
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