Passage Summary: Jones is selling a house to Smith and agreed to only pay for repairs on the roof or the parts of the house that hold the roof up. Because of the house's design, the only walls holding up the roof are the ones on the outside.

Reasoning: The sales contract limits the seller's liability to the roof and its supporting components, and in this specific house, only the exterior walls support the roof.

Analysis: This is a classic Must Be True scenario that relies on a process of elimination based on definitions. We are told Jones is responsible *only* for the roof and roof-supporting components, and we are told *only* the exterior walls support the roof. Therefore, it must be true that Jones is not responsible for any defects found in the interior walls. When navigating the choices, keep a close eye on the 'only' and 'not responsible' qualifiers to ensure you don't overextend the seller's liability. It’s a bit like a legal 'gotcha'—if it doesn't hold up the roof, Jones isn't paying for it.