Q: In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.
Sentence1: Brian took a glass to the sink. Sentence2: He turned the sink on and watched it flow. Sentence3: He put the glass right under the water. Sentence4: The water filled the glass to the top. Sentence5: Brian removed the glass and turned off the sink.
A:
Brian