GWD19-28请帮忙~~~~~想不通哦

Q28（问问问）:

Editorial in Krenlandian Newspaper:

Krenland’s steelmakers are losing domestic sales because of lower-priced imports, in many cases because foreign governments subsidize their steel industries in ways that are banned by international treaties.  But whatever the cause, the cost is ultimately going to be jobs in Krenland’s steel industry.  Therefore, it would protect not only steel companies but also industrial employment in Krenland if our government took measures to reduce cheap steel imports.

Which of the following, if true, most seriously weakens the editorial’s argument?

1. Because steel from Krenland is rarely competitive in international markets, only a very small portion of Krenlandian steelmakers’ revenue comes from exports.

2. The international treaties that some governments are violating by giving subsidies to steelmakers do not specify any penalties for such violations.

3. For many Krenlandian manufacturers who face severe international competition in both domestic and export markets, steel constitutes a significant part of their raw material costs.（这个感觉像加强！！！）

4. Because of advances in order-taking, shipping, and inventory systems, the cost of shipping steel from foreign producers to Krenland has fallen considerably in recent years.

5. Wages paid to workers in the steel industry in Krenland differ significantly from wages paid to workers in many of the countries that export steel to Krenland.

c选项竟然是正确答案。。。请各位帮忙解释一下毫不？

fact: lower-priced steel import=>the cost is the jobs of  Krenland's steel industry

conclusion: reduce cheap steel imports will benefit the companies and industry employment

因果关系存在，要削弱，则因（为事实） +否果，因推不出否果，则他因存在;

A. 无关选项（侧面加强事实）

B. 无关选项（侧面加强事实）

C. 减少低价钢铁进口会影响manufacturer的竞争力=〉造成失业

D. 弱support

E. 小无关，纠缠果之因素二