Since the city council sent a letter to the residents of

Since the city council sent a letter to the residents of Newport on the danger to the environment of smoke from beach firepits, residents have cut their use of beach firepits by 20 percent. Obviously the city council's letter was responsible for the residents' decision to reduce their consumption of firewood.

The author relies on which one of the following to advance his argument?

A) When it sent the letter, the city council predicted a reduction in the consumption of firewood.

B) The cost
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