The AI agrees with the suggested answer A, which states that a flexconfig object for NetFlow must be configured on the Cisco FTD to meet this requirement.
Reasoning: The primary method for configuring advanced features like NetFlow on Cisco FTD, especially when direct GUI options are limited, involves using FlexConfig objects. FlexConfig allows you to push custom CLI configurations to the FTD, enabling features that aren't directly supported in the Firepower Management Center (FMC) GUI. To configure NetFlow, you define the necessary CLI commands within a FlexConfig object, specifying the NetFlow destination and other parameters.
Why other options are incorrect:

B. interface object to export NetFlow: While interface objects are crucial for network configuration, they don't directly handle NetFlow configuration. NetFlow requires specific settings, like the collector IP and export parameters, which are configured via CLI and deployed through FlexConfig.
C. security intelligence object for NetFlow: Security intelligence objects focus on threat intelligence and reputation-based filtering, not NetFlow configuration.
D. variable set object for NetFlow: Variable sets are used for defining reusable variables within the FMC, not for configuring NetFlow itself.

Cisco documentation supports configuring NetFlow using FlexConfig objects on FTD devices, reinforcing this approach. FlexConfig objects allow you to apply custom configurations, including NetFlow settings, which are essential for exporting NetFlow data to a collector like Cisco Stealthwatch.

Configuration Steps:

Navigate to Objects > FlexConfig > FlexConfig Objects in the FMC.
Create a new FlexConfig object to define the NetFlow export configuration.

This configuration ensures that NetFlow traffic is correctly exported from the Cisco FTD device to Cisco Stealthwatch for behavioral analysis.

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