Defense Department analysts worry that the ability of the United States to wage a prolonged war would be seriously endangered if the machine-tool manufacturing base shrinks further. Before the Defense Department publicly connected this security issue with the import quota issue, however, the machine-tool industry raised the national security issue in its petition for import quotas.

Which of the following, if true, contributes most to an explanation of the machine-tool industry's raising the issue above regarding national security?

• AWhen the aircraft industries retooled, they provided a large amount of work for too builders.  
• BThe Defense Department is only marginally concerned with the effects of foreign competition on the machine-tool industry.  
• CThe machine-tool industry encountered difficulty in obtaining governmental protection against imports on grounds other than defense.  
• DA few weapons important for defense consist of parts that do not require extensive machining.  
• ESeveral federal government programs have been designed which will enable domestic machine-tool manufacturing firms to compete successfully with foreign toolmakers.