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: Mars Hills, Crater Yield Evidence of Flowing Water (Reuters) Reuters - The hills of Mars yielded more\tantalizing clues about how water shaped the Red Planet in\tests by NASA's robotic geologist, Spirit, while its twin,\Opportunity, observed the deep crater it climbed into two\months ago, scientists said on Wednesday.

Sci/Tech