Match the books with their authors:
| \(\textbf{List\ I\ (Books)}\) | \(\textbf{List\ II\ (Authors)}\) |
|---|---|
| (a) A Farewell to Arms | 4. Ernest Hemingway |
| (b) Moby Dick | 2. Herman Melville |
| (c) To Kill a Mockingbird | 1. Harper Lee |
| (d) Wuthering Heights | 3. Emily Bronte |
What is 'X' in the following table?