四、閱讀測驗
　　These days, food safety has become a big issue and a major public concern. People are worried about the overuse of chemicals on plants and livestock. Because of increasing health awareness, the number of people switching from traditional food to organic food is on the rise.
　　It is usually thought that chemicals used on plants and animals are harmful for a person’s health. Unlike traditional farms, organic farmers use natural methods to control insects and diseases on their agriculture. Animals like pigs and chickens on organic farms are kept in open spaces so that they may walk around and therefore be better cared for. In addition, they are not fed the type of medicine that helps them grow or recover from illness very quickly. Fruits and vegetables are also planted in such a way where only natural substances are used to make them grow well.
　　Supporters claim several advantages in choosing organic food, such as no chemicals, ecofriendliness, high nutritional values, and better taste. On the other hand, opponents note the disadvantages of organic food. First, organic food is usually more expensive than non-organic food. Second, organic food is produced using no artificial preservatives, and as such it may go bad more quickly. Third, it is not easy to find organic food at every store. Finally, some studies have questioned whether organic food is truly more nutritious than traditional food.
　　Is it really good and safe to eat organic food? The answer may depend upon one’s personal choice. 
36. What is the passage mainly about?
(A) The origin of organic food including its prices in various stores.
(B) The purpose of having organic food including how to cook.
(C) The types and numbers of organic products including where to purchase them.
(D) The introduction of organic food, including its growing processes and pros and cons.