How are logs forwarded when FortiAnalyzer is using aggregation mode?

How are logs forwarded when FortiAnalyzer is using aggregation mode?
A . Logs are forwarded as they are received and content files are uploaded at a scheduled time.
B . Logs and content files are stored and uploaded at a scheduled time.
C . Logs are forwarded as they are received.
D . Logs and content files are forwarded as they are received.

Answer: B