我自己也不知道哪个是对的，请大家教教我吧！

Q2:

Guidebook writer:  I have visited hotels throughout the country and have noticed that in those built before 1930 the quality of the original carpentry work is generally superior to that in hotels built afterward.  Clearly carpenters working on hotels before 1930 typically worked with more skill, care, and effort than carpenters who have worked on hotels built subsequently.

Which of the following, if true, most seriously weakens the guidebook writer’s argument?

1. The quality of original carpentry in hotels is generally far superior to the quality of original carpentry in other structures, such as houses and stores.

2. Hotels built since 1930 can generally accommodate more guests than those built before 1930.

3. The materials available to carpenters working before 1930 were not significantly different in quality from the materials available to carpenters working after 1930.

4. The better the quality of original carpentry in a building, the less likely that building is to fall into disuse and be demolished.

5. The average length of apprenticeship for carpenters has declined significantly since 1930.

   Answer: D

G作家认为房子越老，质量越好而实际是因果颠倒，因为房子质量好，所以保存的时间才长久，至今岿然不动。

the more the more 八成是正确答案
两元素削弱，这是典型的因果颠倒削弱方式