病因调查的思路可包括（）A、从临床症状入手，寻找病因假设B、从疾病分布特征入手，寻找

居民的消费受很多因素影响，其中最主要的是[ ]

①收入水平

②商品的质量

③物价水平

④商品的外观、性能等

⑤消费者的购物心理

A、①②③

B、②③④

C、①③

D、①②③④⑤

用实验证实DNA的半保留复制的是（）。

A.Temin

B.Watson和Crick

C.Okazaki

D.Meselson和Stahl

E.Kornberg

简述鸡的生物学特点和行为习性。

藁本的功效是（）

A．利水消肿

B．祛风胜湿

C．温肺止咳

D．行气宽中

E．散风寒，通鼻窍

OOP languages that create objects, such as (1) and (2) are beginning to take hold as viable tools for programmers. To effectively reuse objects, programmers need a place to store them such as an ODBMS or a RDBMS with object oriented extensions.
Databases that handle object data not only let user store and retrieve (3) data, but also let them store objects created by OOP languages, to facilitate rapid software development and reuse, and let them (4) new multimedia applications combining multiple data types.
RDBMS vendors have developed new extensions to existing DB technology to accommodate the most common forms of (5) data.

A．C++

B．BASIC

C．PASCAL

D．structured