OG-CR-13 I need you help !

Fincher

13. 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?
(A) When the aircraft industries retooled, they provided a large amount of work for tool builders.
(B) The Defense Department is only marginally concerned with the effects of foreign competition on the machine-tool industry.
(C) The machine-tool industry encountered difficulty in obtaining governmental protection against imports on grounds other than defense.
(D) A few weapons important for defense consist of parts that do not require extensive machining.
(E) Several federal government programs have been designed which will enable domestic machine-tool manufacturing firms to compete successfully with foreign toolmakers.

不是很理解，大家能不能每个选项不管对错，用中文帮我解释一下，谢谢！

Angie安

，