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: Nancy was a cigarette smoker. Sentence2: Her best friend smoked as well. Sentence3: As they got older, Nancy's friend got cancer. Sentence4: Nancy became alarmed and treated it as a wake up call. Sentence5: Nancy quit smoking after her friend died.
A:
Best friend, Nancy