This type of index can be comprised of multiple columns in a
Solution
3.) (A) Non-clustered.
clustered indexes should have a unique key (an identity column I would recommend) as the first column. While a non-clustered index, on the other hand, does not alter the way the rows are stored in the table. It creates an object within the table that contains the columns selected for indexing and a pointer . It is like an index in the last pages of a book, where keywords are sorted and contain the page number to the material of the book for faster reference.
4.) (d) None of the above.
Denormalizing of Database is done for improving query performance,speeding up reporting,computing values at larger side, and maintaining history.
5.) (d)In order for this relationship to be implemented , the DBA will have to create a new Mandatory relationship object.

