The statement that is correct about the Sticky Decision Function is It is not supported with either the Performance pack of a hardware based accelerator card. The Sticky Decision Function (SDF) is a feature that ensures that packets from the same connection are handled by the same cluster member in a Load Sharing configuration. However, SDF is not compatible with SecureXL acceleration, which is enabled by default or by using a Performance pack or a hardware based accelerator card4. The other statements are either incorrect or outdated about SDF. References: Check Point R81 ClusterXL Administration Guide, Sticky Decision Function - Check Point CheckMates

What are types of Check Point APIs available currently as part of R81.20 code?
The types of Check Point APIs available currently as part of R81.20 code are:
* Management API: This API allows you to automate and orchestrate various management tasks, such as creating and modifying objects, installing policies, generating reports, etc. The Management API can be accessed via CLI, Web Services, or GUI clients.
* Threat Prevention API: This API allows you to interact with the Threat Prevention software blades, such as Anti-Virus, Anti-Bot, Threat Emulation, etc. The Threat Prevention API can be used to query and update indicators, upload files for emulation, retrieve verdicts and reports, etc.
* Identity Awareness Web Services API: This API allows you to integrate external identity sources with the Identity Awareness software blade, which provides identity-based access control for network traffic. The Identity Awareness Web Services API can be used to send identity and session information to the Security Gateway, query identity information from the Security Gateway, etc.
* OPSEC SDK API: This API allows you to develop custom applications that can communicate with Check Point products using the OPSEC protocol. The OPSEC SDK API supports various OPSEC services, such as LEA, CPMI, SAM, ELA, UFP, etc. References: R81 Management API Reference Guide, page 7; [R81 Threat Prevention API Reference Guide], page 7; [R81 Identity Awareness Administration Guide], page 105; [OPSEC SDK R81 Documentation Package].

Check Point's FW Monitor is a powerful built-in tool for capturing network traffic at the packet level. The FW Monitor utility captures network packets at multiple capture points along the FireWall inspection chains.
These captured packets can be inspected later using the WireShark.
References:

It is false that it is not necessary to establish SIC between the primary and secondary management server, since the latter gets the exact same copy of the management database from the prior. In fact, SIC is required between the primary and secondary management server for Management HA to work properly. SIC ensures secure communication between the management servers and allows the standby server to receive updates from the active server. Without SIC, the standby server will not be able to synchronize with the active server and will not be ready to take over in case of a failover.
Reference:
Solved: Management HA - Check Point CheckMates, section "Synchronizing Active and Standby Servers" CheckPoint Management Server R81 HA Configuration | Udemy, section "How to set it up in the PNET lab environment" Check Point R81, section "Management High Availability"