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: 18,000 troops begin winter offensive in Afghanistan against &lt;b&gt;...&lt;/b&gt; The 18,000 US troops in Afghanistan have begun a new offensive to hunt Taliban and al-Qaida militants through the country #39;s harsh winter, aiming to sap their strength ahead of planned spring elections, the American military said Saturday.

World