D. Because the majority of the reporting is going to be performed by using the storage location, it would be the likely candidate. The clustered index represents the physical order of the data and would minimize sorting operations when deriving the output. For more information, see the section "Maintaining Order by Using Indexes."
B, C, D, E. All these options have activities that provide or alter data so that they do not have to be performed as entry operations. In the case of NULL, data does not need to be provided, possibly because the column contains noncritical information. For more information, see the section "Defining SQL Server Tables."
A. To obtain the physical storage sequence of the data, you must use a clustered constraint or index. Although a primary key would also provide for the desired level of uniqueness, it is not the appropriate key for this table. For more information, see the section "Maintaining Order by Using Indexes."
D. The primary key is usually the clustered index of a table. The clustered index indicates the physical order of the data. A low fill factor leaves more room for updates. For more information, see the section "Maintaining Order by Using Indexes."
C. INSTEAD OF triggers are required for this task because you must check for constraint violations before the update occurs. If there are constraint violations, AFTER triggers will not fire. Most likely, you need to implement INSTEAD OF INSERT or INSTEAD OF INSERT and UPDATE triggers. When trigger actions are listed, such as an INSERT TRigger, you cannot know for sure whether it is an INSTEAD OF or AFTER trigger, but you should assume that it is a FOR or AFTER TRigger if not specifically mentioned. For more information about the order in which triggers and constraints are applied see the information on sp_settriggerorder in SQL Server Books Online.
D. A single trigger can be used to perform validation on more than one event, such as INSERT and UPDATE. For more information about the differences between trigger types, see the section "Using DML and DDL Triggers."
A. You can use a DDL trigger applied to the creation of the database to have this information recorded. See the section "Using DML and DDL Triggers."