请教移到GWD的逻辑题

fangfanggmat

Q38

Many residents of Calovia are committed to using productscontaining recycled materials.  Soon these consumers will get help inidentifying such products from a book being published by the Caloviangovernment.  The book offers a comprehensive listing, by product type andbrand, of goods sold in Calovia that contain recycled material. Therefore, publication of the book will almost certainly increase the use ofproducts containing recycled materials in Calovia.

Which of the following, if true, most strengthens theargument?

• Proceeds from the sale of the     book are not expected to exceed the cost of its publication.
• For numerous types of products,     there are many brands that use recycled materials, although their     manufacturers and distributors do nothing to advertise those brands'     recycled content.
• For many materials, such as     plastics, the recycling process results in a lower grade of material with     a correspondingly different range of uses.
• For many types of products     listed in the book, all the brands available in Calovia use recycled     materials.
• Many manufacturers of products     that contain recycled materials vary the proportion of recycled materials     in those products in response to changes in price and availability.
• 
  
• 答案是B。我想选D.
• 这个题是要加强：书的发行会增加环保产品的使用。
• B:很多品牌已经在使用环保材料了，虽然厂家和经销商没宣传（我觉得无关）
• D：对书上列出的所有使用环保材料的产品（因为书上写了，方便大家知道，从而去买，从而增加环保产品的使用）
  

谢谢！

alzn2765

因果推理找假设：

前提（因）：The book offers a comprehensive listing, by product type andbrand, of goods sold in Calovia that contain recycled material.
结论（果）：publication of the book will almost certainly increase the use of products containing recycled materials in Calovia

明显结论成立需要一个assumption：在书出版之前，有一些使用recycled material的brand是Calovia的消费者所不知道的，所以在书出版之前，这些brand因为人们不知道他们用的是recycled material而用的少，所以人们通过书知道了之后而去使用这些brand，才能使use of products containing recycled materials in Calovia增加。

如果Calovia本来有100个用recycled material的brand，而这100个brand Calovia的消费者都知道，那么即使书把这100个brand列进去，products containing recycled materials的使用也不会增加。

B就是这么一个assumption：有些的确是使用recycled materials的厂商，并没有通过广告等方式让消费者知道他们使用的是recycled materials。这样出书才有意义。

这题看起来是加强题，实际是假设题。