which two statements best describe the difference between active mode monitoring and fast mode monitoring?

In a PfR environment, which two statements best describe the difference between active mode
monitoring and fast mode monitoring? (Choose two.)

A.
Active mode monitoring can monitor and measure actual traffic via NetFlow data collection.

B.
Fast mode monitoring can measure bursty traffic better than active mode.

C.
Active mode monitoring uses IP SLA probes for the purpose of obtaining performance
characteristics of the current WAN exit link.

D.
Fast mode monitoring uses IP SLA probes via all valid exits continuously to quickly determine an
alternate exit link.