gmatimothy
Can anyone explain why (B) is not the correct answer here?
"Under the current standards that museums use when storing Renaissance oil paintings, those paintings do not deteriorate at all."
Is it wrong because the paintings can be deteriorated but not endangered?
(B) is incorrect in two ways.
One is that, as you said, what the passage is about is not quite the same as what choice (D) is about, "do not deteriorate at all."
The passage is about events, such as wide fluctuations in temperature and humidity, that could cause damage to painitings. On the other hand, the deterioration mentioned by (D) could be a breakdown over time of a painting that would occur even under stable, normal conditions.
Then, an even more clear reason why (D) is wrong is that the conclusion is that museums will not endanger the paintings by ceasing to conform to the current standards. It's not necessary to assume that paintings do not deteriorate under the current standards to conclude that museums can cease to conform to those standards.
In other words, why would you have to assume that the standards are perfect to conclude that you don't have to use them?