Correct Answer: A
In the context of Cisco UCS, filters are used in query strings to specify criteria for retrieving information about compute blades. The correct filter is "(num_of_cpus eq 2) and (discovery eq complete)" because it specifies that we are looking for compute blades with exactly two CPUs (num_of_cpus eq 2) and where the discovery status is 'complete' (discovery eq complete). This ensures that only compute blades that have been fully discovered by UCS Manager and have exactly two CPUs will be returned by the query.
References:
* Implementing Automation for Cisco Data Center Solutions (DCAUI)
* Cisco Learning Network - Data Center Training Videos