The Plain of Jars is an archaeological site in the Southeast Asian country of Laos At the site hundreds of large stone jars ranging in size from one to three meters are scattered across the countryside These numerous large containers are around 2 000 year

In this set of materials, the reading passage explains three possible theories about the purpose of the Plain of Jars on an archaeological site. However, the lecturer believes that despite these theories, they are still mysterious, and scientists are uncertain about them. Then he provides some evidence to refute them all. First of all, it is mentioned in the article that people used the jars for fermentation to celebrate special ceremonies such as a great victory. On the contrary, the lecturer asserts that clay pots also can serve this purpose while the Plain of Jars were made of stone. It was difficult, time-consuming, and expensive to make such a huge jar by a stone while clay jars were accessible. Hence, it is unconvincing that ancient people used them for such a purpose. Furthermore, the author of the passage claims that another reasonable theory is that they have been used for water storage. In contrast, the professor points out that although jars were found near trade routes, there were also rivers and streams close to those routes. It shows that traveling traders did not need to have other sources of water when they could easily have access to freshwater nearby. In fact, it is impossible to keep water in large jars near rivers and streams. Finally, the passage states that people may use them as tombs to place human remains. Conversely, the professor argues that even though some metal tools, jewelry, and glass beads have been found in some jars, nobody can assume they belong to dead people since researchers did not find any covers on or near jars. It was necessary to protect dead bodies from weather and animals, and without covering, it was impossible. Therefore, people did not use the jars as tombs.