The deployer is a Splunk Enterprise instance that distributes apps and other configurations to the members of a search head cluster1.

The deployer cannot share functionality with any other Splunk Enterprise instance, including the license master, the master node, or the monitoring console2.

However, the search head cluster members can share functionality with the master node and the monitoring console, as long as they are not designated as the captain of the cluster3.

Therefore, the correct answer is B. License master, as it is the only instance that cannot share functionality with the deployer under any circumstances.