A certain type of dinnerware made in Ganandia contains lead.

Lead can leach into acidic foods, and Ganandians tend to eat

highly acidic foods.  However, the extreme rarity of lead poison-

ing in Ganandia indicates that the dinnerware does not contain

dangerous amounts of lead.

 Which of the following, if true, most seriously weakens the argu-

ment above?

      The dinnerware is produced exclusively for sale outside

       Ganandia. 

     Ganandian foods  typically are much more acidic than

       foods anywhere else in the world.  

     The only source of lead poisoning in Ganandia is lead

       that has leached into food. 

     Most people who use the dinnerware are not aware that

       it contains lead. 

     Acidic foods can leach lead from dinnerware even if that

       dinnerware has a protective coating. 

答案 A