This is the source that is the most likley to give credible information about changes to international trade laws. This is because of two important factors. The first one is that newspapers are intended to report news, therefore, they are more likely to report on this type of event. The second one is the fact that this is the most recent publication, so it is likely to have the most recent information.
All the options besides Option see are much older. That is fore sure is already something to make you go for the newest information. Besides that, magazines tend to contain information that people can rely on, since it is a reporter's job, mostly. When you combine the fact that it is recent news and it is from a Magazine, it seems much more trustworthy than a random interview, or an online exposé or a book (since journalistic magazines are working on bringing news all the times and books have other function) all from many years ago.
C. A magazine article written in May 2013
