推断题。说明文的题目一定和文章的说明对象有直接关系，所以做题之前了解本文的说明对象有重要意义，即raw and whole foods好、cooked and refined foods不好。而第二段中指出，natural enzymes是raw food中重要的成分，好处是什么，破坏了以后坏处是什么。所以根据这样的思路，答案为A选项。注意中文注释再次发挥极为重要的作用。

68. Processed foods are unhealthy because they __________.

A. destroy body’s cells

B. may lead to obesity

C. are difficult to digest

D. stop body’s metabolism

答案：B

细节题。第三段一开始提到问题中的processed food，所以答案可以轻易的定位至第三段。此段一直提到各种负态度描述，所以关注最后一句的the result is weight gain and obesity，可以很容易的选出答案B选项。此段文章内容非常不好理解，但是把握阅读理解的要求，关注文章中的重点信息，题目其实并不难。如何在短时间内发掘文章中的重点信息，不受大量冗余信息干扰再次很重要，这是阅读理解考察的主要方向。

69. What is the main purpose of this passage?

A. To warn people of the problem of obesity.

B. To advocate eating more raw and whole foods.

C. To inform people of the harm of processed foods.

D. To tell the differences between raw and processed foods.

答案：B

主旨题。只要知道文章的说明对象是raw and whole foods，此题就不难确定答案B选项。processed foods是用来和raw and whole foods对比以突出后者的，所以排除C选项和D选项。至于A选项的信息在68题已经考过了，再次出题的可能性就不大。

70. What is likely to be talked about following the last paragraph?

A. Different causes of acid accumulation.

B. Correct ways to cook raw foods.

C. Suitable types of raw and whole foods.

D. Active approaches to avoid acid.