Explanation:

- Option 1: Mary Shelley

- Mary Shelley is known for writing "Frankenstein." She wasn't the author of "To Kill a Mockingbird."

- Option 2: George Orwell

- George Orwell wrote "1984" and "Animal Farm." He did not write "To Kill a Mockingbird."

- Option 3: Harper Lee

- Harper Lee is the author of "To Kill a Mockingbird," a novel that explores themes of racial injustice and moral growth in the American South.

- Option 4: Charles Dickens

- Charles Dickens wrote classics like "A Tale of Two Cities" and "Great Expectations." He did not write "To Kill a Mockingbird."