A few people who are bad writers simply cannot improve their writing, whether or not they receive instruction. Still, most bad writers can at least be taught to improve their writing enough so that they are no longer bad writers. However, no one can become a great writer simply by being taught how to be a better writer, since great writers must have not just skill, but also talent. Which one of the following can be properly inferred from the passage above? ['All great writers had to be taught to become better writers.', 'Some bad writers can never become great writers.', 'All bad writers can become better writers.', 'Some great writers can be taught to be even better writers.']