What needs to be defined in the presentation layer?

A customer frequently queries multiple dimension tables without a measure. What needs to be
defined in the presentation layer?

A.
Logical Key

B.
Implicit Fact Column

C.
Alias

D.
Logical Column Name

E.
Custom Display Name

Explanation:
Metadata Repository Builder’s Guide

http://download.oracle.com/docs/cd/E21764_01/bi.1111/e10540/toc.htm
http://download.oracle.com/docs/cd/E21764_01/bi.1111/e10540.pdf
Setting an Implicit Fact Column in the Subject Area
For each subject area in the Presentation layer, you can set an implicit fact column. The
implicit fact column is added to a query when it contains columns from two or more
dimension tables and no measures. The column is not visible in the results. It is used
to specify a default join path between dimension tables when there are several possible
alternatives or contexts.