Scenario: A Citrix Administrator is configuring a Citrix ADC high availability (HA) pair.

Correct Answer: C. Configure HA fail-safe mode on each Citrix ADC independently.

Short Explanation with reference:

HA fail-safe mode is a feature that allows the Citrix ADC appliance to continue processing traffic even if both nodes in an HA pair become unavailable or fail a health check. This prevents the appliance from dropping existing connections or rejecting new requests, and ensures that the business websites are always available. HA fail-safe mode can be enabled or disabled on each node independently by using the -failSafe option in the CLI or by checking or unchecking the Fail-Safe Mode check-box in the GUI. Therefore, the correct answer is C. Configure HA fail-safe mode on each Citrix ADC independently.

Configuring high availability fail-safe mode | NetScaler