Definition: In this task, you are given a news article. Your task is to classify the article to one out of the four topics 'World', 'Sports', 'Business', 'Sci/Tech' if the article's main topic is relevant to the world, sports, business, and science/technology, correspondingly. If you are not sure about the topic, choose the closest option. Note that URLs in the text have been replaced with [Link].
Input: Official Campaign Opens in Afghan Presidential Poll (Reuters) Reuters - The official month-long campaign for\Afghanistan's first-ever direct presidential election opened on\Tuesday in what will be a major test of U.S.-led\nation-building efforts since the 2001 ouster of the Taliban.

World