A. They are tied to a specific statement or SQL id.
B. They instruct the maintenance job to collect missing statistics or perform dynamic sampling to generate a more optimal plan.
C. They are used to gather only missing statistics.
D. They are created for a query expression where statistics are missing or the cardinality estimates by the optimizer are incorrect.
E. They instruct the optimizer to create only column group statistics.
F. Improve plan accuracy by persisting both compilation and execution statistics in the SYSAUX tablespace.

A. It executes successfully and creates an UNDO tablespace in hr_pdb.
B. It falls and reports an error because there can be only one undo tablespace in a cdb.
C. It fails and reports an error because the CONTAINER=ALL clause is not specified in the command.
D. It fails and reports an error because the CONTAINER=CURRENT clause is not specified in the command.
E. It executes successfully but neither tablespace nor the data file is created.