Bad Qubits — Learn Quantum by Doing

Multiple choice

For a stabilizer code, the logical Pauli operators Xbar and Zbar are elements of the normalizer (not in S) that must satisfy two commutation requirements. Which pair of requirements correctly captures them?

Xbar and Zbar each ANTICOMMUTE with every stabilizer generator, and COMMUTE with each other
Xbar and Zbar both COMMUTE with every stabilizer generator AND COMMUTE with each other
Xbar and Zbar each COMMUTE with every stabilizer generator (so they preserve the codespace and produce no syndrome), but ANTICOMMUTE with each other (so they act as a genuine qubit's X and Z)
Xbar and Zbar are themselves stabilizer generators, so they fix every codeword