You need to reduce the report processing time and minimize the growth of the database

You are reviewing the design of an existing fact table named factSales, which is loaded from a SQL Azure
database by a SQL Server Integration Services (SSIS) package each day. The fact table has approximately 1
billion rows and is dimensioned by product, sales date, and sales time of day

The database administrator is concerned about the growth of the database. Users report poor reporting
performance against this database. Reporting requirements have recently changed and the only remaining
report that uses this fact table reports sales by product name, sale month, and sale year. No other reports will
be created against this table. You need to reduce the report processing time and minimize the growth of the
database. What should you do?

A.
Partition the table by product type.

B.
Create a view over the fact table to aggregate sales by month.

C.
Change the granularity of the fact table to month.

D.
Create an indexed view over the fact table to aggregate sales by month.

Explanation:
checked against both