Discharge instructions for clients receiving tricyclic antidepressants include which of the following information

A．Don't consume alcohol.

B．Restrict fluid and sodium intake.

C．It's safe to continue taking during pregnancy.

D．Discontinue if dry mouth and blurred vision occur.

在用例建模的过程中，若几个用例执行了同样的功能步骤，这时可以把这些公共步骤提取成独立的用例，这种用例称为 (42) 。在UML的用例图上，将用例之间的这种关系标记为 (43) 。

A．association

B．extends

C．uses

D．inheritances