Which of the following best describes the attitude of the author of the passage toward the first theory described in答案解析-雷哥GRE

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Canali, lava channels on Venus thousands of kilometers long (compared to Earth's sinuous rillesof a few hundred kilometers) and 1 to 2 kilometers wide, have perplexed scientists. One interpretation of canali origins is that ordinary basaltic silicate lava formed them. Silicate lava is quite erosive initially but rapidly cools and solidifies. Calculations indicate that Venus’ dense atmosphere would accelerate convective cooling, preventing these lavas from flowing thousands of kilometers if erupted in channel-eroding quantities. Alternatively, the volume of lava needed to flow the required distance would have buried the channels we now observe. Therefore, silicate lavas probably cannot form canali. In another interpretation, canali-forming lavas had low viscosity, therefore high mobility, and temperatures closer to their Venusian surroundings, thereby decreasing convective cooling. No silicate lavas possess this combination, but rare carbonatite lavas exhibit both properties: melting points around 500 degrees Celsius and

viscosities like water's. Such lava on Venus would harden slowly,allowing sediments to sink and channels to erode laterally.

Which of the following best describes the attitude of the author of the passage toward the first theory described in the passage?