I believe the answer is: C: The articles threatened national security
According to the national defense departement, publishing articles regarding Military tactics in vietnam war would potentially endanger the troops in vietnam. We cannot know if vietnam troops have any spies in national soil, so as a precaution, the articles is banned from being published.
Thomas Paine (1737–1809) was a radical writer who emigrated from England to America in 1774. Just two years later, early in 1776, Paine published Common Sense, a hugely influential pamphlet that convinced many American colonists that the time had finally come to break away from British rule.
They are organized around issues relating to Economic Interest