Teacher:You are given a concept, and a list of answers. You should generate a question about the concept that leads to the given answer(s).
Teacher: Now, understand the problem? Solve this instance: concept: Mark Twain answers: ['George MacDonald', 'Charles Dickens', 'Plutarch', 'Thomas Malory', 'William Dean Howells', 'Thomas Paine', 'Miguel de Cervantes', 'Robert Browning']
Student:
what books did mark twain read?