A GTM System would like to ensure that a given LTM System is reachable and iQuery communication is allowed prior to sending it client request. What would be the simplest monitor template to use?

The TCP monitor only verifies that a TCP connection can be established to a specified port and has no capability to validate iQuery protocol communication.

The ICMP monitor only confirms basic network reachability via ping echo and does not test whether iQuery communication is permitted or functional.

The HTTP monitor checks for valid HTTP responses from a web service endpoint and cannot verify the iQuery protocol used between GTM and LTM.

The BIG-IP monitor performs a combined check: it first verifies ICMP reachability to confirm the LTM is accessible on the network, then validates that iQuery communication - the F5 proprietary protocol used to exchange health and performance data between GTM and LTM - is functioning. No other standard monitor template tests iQuery, making the BIG-IP monitor the simplest and most direct option for this specific requirement.

The SNMP monitor polls SNMP OIDs to retrieve device metrics and does not test iQuery communication between the GTM and LTM Systems.