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: Critics Say Putin Must Address Security Corruption President Vladimir Putin #39;s move to enhance his power in response to a wave of terrorism does not take on the real problem: the corrupt and unreformed security services that 

World