Which statement applies to Flexible NetFlow? 

Answer options:

A. Flexible NetFlow uses seven key fields in IP datagrams to identify the flow.
B. Flexible NetFlow uses key fields of IP datagram to identify fields from which data is captured.
C. User-defined flows can be defined in Flexible NetFlow.
D. Flexible NetFlow cannot be used for billing and accounting applications.
E. Flexible NetFlow does not have any predefined records.

C