What is the significance of the setting "Summarize project based on high level resource planning”?

What is the significance of the setting “Summarize project based on high level resource planning”?

A.
Summarized project data will reflect Top Down plans.

B.
Summarized project data will reflect Bottom Up plans.

C.
Summarized project data will reflect actuals pushed from another application.

D.
Summarized project data will be monetized.

Explanation:
Typically, use the High Level Resource Planning option for future projects that are
currently planning only high-level resource allocation requirements, or for projects that are
underway, but for which you do not want to assign resources at a detailed activity-level.
Note: You can specify several default values that will be used for activities when you create new

projects.
One such setting is ‘Summarize Project Based on’.
‘Summarize Project Based on’ determines whether the Summarizer calculates and displays rolledup data based on resource assignments at the activity or project level.
Reference: Set Project Default Options
http://docs.oracle.com/cd/E17462_01/Web_Access/Help/en/Projects/Tasks/pm_p_setdefaults.htm