终端用户可以通过修改标准程序以获取原本无法直接获取的财务和作业数据的子集，与此相关的最大风险是：
A．所获取的数据可能不完整或缺乏时效性。
B．数据定义可能过时。
C．主机数据可能被终端用户的更新活动所破坏。
D．重复下载可能会耗尽终端用户微机的存储容量。
参考答案：A
解析：
A．正确。终端用户对主机数据结构及之间的关联不可能很精通，因此通过修改标准程序所获取的数据就可能不完整；由于获取的数据保存在本地微机中，而主机数据是实时变化的，因此微机中的数据可能不是最新的数据，即缺乏时效性。
B．不正确，数据定义不会因为终端用户的数据查询操作而改变。
C．不正确，终端用户获取数据子集的过程下包含更新操作，不会导致对主机数据的破坏。
D．不正确，重复下载的数据通常会相互覆盖，因此也不会耗尽终端用户微机的存储容量。
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