Question ID:PT85 S2 Q16 Passage:Scientist: An orbiting spacecraft detected a short-term spike in sulfur dioxide in Venus‚ s atmosphere. Volcanoes are known to cause sulfur dioxide spikes in Earth‚ s atmosphere, and Venus has hundreds of mountains that show signs of past volcanic activity. But we should not conclude that volcanic activity caused the spike on Venus. No active volcanoes have been identified on Venus, and planetary atmospheres are known to undergo some cyclical variations in chemical composition. Stem:Which one of the following, if true, most weakens the scientist's argument? Correct Answer Choice:AChoice A:Conditions on Venus make it unlikely that any instrument targeting Venus would detect a volcanic eruption directly. Choice B:Evidence suggests that there was a short-term spike in sulfur dioxide in Venus's atmosphere 30 years earlier. Choice C:Levels of sulfur dioxide have been higher in Venus's atmosphere than in Earth's atmosphere over the long term. Choice D:Traces of the sulfur dioxide from volcanic eruptions on Earth are detectable in the atmosphere years after the eruptions take place. Choice E:Most instances of sulfur dioxide spikes in the Earth's atmosphere are caused by the burning of fossil fuels.