关于普萘洛尔抗心绞痛作用的错误叙述（）

A.久用后不宜突然停药

B.对变异型心绞痛效果好

C.与硝酸甘油合用有协同作用

D.对伴有心律失常的患者效果好

E.对伴有高血压的患者效果好

WebSQL is a SQL-like (6) language for extracting information from the web. Its capabilities for performing navigation of web (7) makes it a useful tool for automating several web-related tasks that require the systematic processing of either all the links in a (8) , all the pages that can be reached from a given URL through (9) that match a pattern, or a combination of both. WebSQL also provides transparent access to index servers that can be queried via the Common (10) Interface.

A．hypertext

B．page

C．protocol

D．operation