The recent boom in new home construction has finally begun to taper off. Developers are not buying land, contractors are finding themselves going without work for longer periods, and banks are issuing fewer mortgages. People must not be as interested in buying new homes as they were even six months ago.

Which of the following indicates a flaw in the reasoning above?
"¢ Interest rates for home mortgages have increased significantly over the past six months.
"¢ The average size of a new home has increased significantly over the past several years.
"¢ Sales of condominiums have increased over the past six months.
"¢ The cost of materials such as lumber and cement has decreased over the past year.
"¢ Sales of other big-ticket items, such as automobiles and boats, has remained steady over the past year.

OA is A. C is out of scope, since the argument relates to interests in NEW homes rather than the old ones.

Could smb explain te difference btw FLAW and WEAKEN questions.

In the above question we use the similar techniques to tackle the FLAW and WEAKEN questions (e.g. we find an alternative explanation). Nevertheless CR bible relates FLAW questions to another group of questions (METHOD of reasoning), which use different techniques. This confuses me a bit.