In ancient times, due to the limitations of the level of political, economic and cultural development, books were not as many and so complicated as today, so the need for reference books is far less urgent than today. What is the most accurate restatement of this passage? ['Politics, economy, and culture in ancient times were less developed than today.', 'Ancient politics had many restrictions on books.', 'The ancients did not need reference books.', 'The need for ancient man-made reference books is not as urgent as modern people.']