Passage Summary: While wood stoves are efficient, they are considered more dangerous because their smoke leaves behind a flammable gunk that can cause chimney fires.

Conclusion: Wood-burning stoves pose a greater safety risk than open fireplaces.

Reasoning: Stoves produce cooler smoke that travels slowly, leading to a higher accumulation of flammable creosote in the chimney.

Analysis: To weaken this argument, we need to find a way to show that fireplaces are actually just as dangerous as, or more dangerous than, wood-burning stoves. The author focuses exclusively on chimney fires caused by creosote, which is a 'narrow' metric for safety. Look for an answer choice that introduces a different, significant danger inherent to fireplaces that stoves avoid, such as the risk of sparks jumping into the room. If fireplaces have a high rate of house fires from flying embers, the creosote build-up in stoves might seem like the lesser of two evils.