Advertisement: Ten years ago, the Cormond Hotel's lobby was carpeted with Duratex carpet while the lobby of a nearby hotel was being carpeted with our competitor's most durable carpet. Today, after a decade in which the two hotels have had similar amounts of foot traffic through their lobbies, that other hotel is having to replace the worn-out carpeting near its lobby entrances, whereas the Cormond's Duratex carpeting has years of wear left in it.

Which of the following, if true, most seriously weakens the force of the advertisement's evidence for concluding that Duratex carpet is more durable than the carpet of its competitor?

• AThe lobby of the Cormond Hotel has five different entrances, but the lobby of the other hotel has only two.  
• BThe carpet of the Cormond Hotel's lobby is not the most durable carpet that Duratex manufactures.  
• CThe other hotel has a popular restaurant that can be reached from outside without walking through the hotel lobby.  
• DThe carpet that is being used to replace carpeting near the other hotel's lobby entrances is not Duratex carpet.  
• EThere is a third hotel near the other two that has not replaced the Duratex carpet in its lobby for more than 15 years.