I think he may be right. But I have not read the whole thing, so I may be wrong.
Explanation:
The simple present, present simple or present indefinite is one of the verb forms associated with the present tense in modern english.
1). Description. Since the paragraph is describing salads without comparing/telling how to make it, the structure is Description.
2). Cause and effect. Since this paragraph is describing how the salad Bars became popular and the effects of it, the structure is cause and effect.
3). Problem and Solution. Since this paragraph is describing how the school lacked nutritional value and how the school fixed it, the structure is problem and solution.
4). compare and contrast. Since this paragraph is comparing the Cobb salad and the taco salad, the structure is compare and contrast.
5). Sequence/order. Since this paragraph is detailing how to make a salad, the structure is sequence/order.