对文献主题进行分析时，以下可选择的指标是（）。A、题目 B、关键词 C、作者 D、引

论述张掖市盐化灌漠土的分布、形成过程、特性及危害？

阅读理解。

      People have strange ideas about food. In the 18th century, Americans never ate tomatoes. They grew them

in their gardens because tomato plants are so pretty. But they thought the vegetable was poisonous. They called

tomatoes "poison apples." 

      President (总统) Thomas Jefferson, however, knew that tomatoes were good to eat. He was a learned man.

He had been to Paris, where he learned to love the taste of tomatoes. He grew many kinds of tomatoes in his

garden. The President taught his cook a way, for a cream of tomato soup (汤). This beautiful pink soup was

served at the President's next dinner party. The guests (客人) thought the soup tasted really good. They never

thought their President would sever his dinner guests poison apples. Jefferson never spoke to his honored guests

about the fact.

1. Which of the following is true? [ ]

A. Americans never ate tomatoes after the 17th century.

B. Even now Americans don't eat tomatoes.

C. It was not until after the 18th century that Americans began to grow tomatoes for food.

D. Americans didn't eat tomatoes before the 19th century.

2. Jefferson was a president of _______. [ ]

A. a European country

B. the United States

C. England

D. France

3. Jefferson learned that tomatoes were good to eat _______. [ ]

A. even when he was a little boy

B. because his parents told him so

C. from books

D. while he was in Paris

4. From the passage we know all the honored guests invited by Jefferson were _______.[ ]

A. people of his own country

B. people from other countries

C. Frenchmen

D. men only

5. According to the passage, which of the following is wrong? [ ]

A. All the guests thought the cream of tomato soup was nice.

B. All the guests thought the soup had a good taste.

C. All the guests thought the taste of the beautiful pink soup was nice.

D. None of the guests ever thought if the soup was poisonous or not.

殡葬服饰是指？

自身免疫溶血性贫血输血宜选（）

A.全血

B.浓缩红细胞

C.血浆

D.三洗红细胞

E.冰冻红细胞

按照管理职能的不同，可以将管理者分为哪些？