Choose the best answer A, B, C or D.
1. Wearable sensors, such as the Fitbit, Nike FuelBand and Jawbone UP, _______ the most important part of the fitness world for the last few years.
2. Scientists have invented artificially intelligent computer systems ____ of answering questions posed in natural language.
3. Users can look ____ locations as well as directions to different places on Google Maps.
4. _____ noodles are a precooked and usually dried block invented by Japanese.
5. The ____,which can travel underwater, is very useful for scientists to learn about the undersea world.
