Task: Question Answering
Input (English): Background Paragraph: A comet tail—and coma—are features visible in comets when they are illuminated by the Sun and may become visible from Earth when a comet passes through the inner Solar System. As a comet approaches the inner Solar System, solar radiation causes the volatile materials within the comet to vaporize and stream out of the nucleus, carrying dust away with them. Separate tails are formed of dust and gases, becoming visible through different phenomena; the dust reflects sunlight directly and the gases glow from ionisation. Most comets are too faint to be visible without the aid of a telescope, but a few each decade become bright enough to be visible to the naked eye. 
Story: Year 2022 would be an interesting year when three comets would get scientists' attention - Comet A, Comet B, and Comet C. Comet A and C are very faint, but Comet B is very bright. Comet A would enter the inner solar system on February 10, 2022 and leave the inner solar system on February 20, 2022. Comet B would enter the inner solar system on February 18, 2022 and leave the inner solar system on February 26, 2022. Comet C would never enter the inner solar system. 
Question: Which comet's materials would steam out of the nucleus, Comet B or Comet C?
Output (English): Comet B.