GMAT Critical Reasoning (CR) | Re: When storing Renaissance oil paintings, museums conform to

Hi Expert,

I am facing hard time for assumption questions such as this. my strategy is to find conclusion , strengthening it with given choices, if we end up more then one choices then use negation test. I used the same for this question and end up with A. I am trying to stay with the basics but not working out some how over here. any help on fact, where it all went wrong???

Thanks !

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