While it is variously referred to as branch, path, or variability identification, in all cases the test designer identifies the various ways the user or external system can execute the use case.

After the previous test, Process a and Process Z diverge, each taking a separate code path, as if both came to a fork in the road and each took a distinct branch.

Ignoring the root element (in this case,), you then follow a path up the tree from branch to smaller branch until you can go no farther.