Bad Qubits — Learn Quantum by Doing

Multiple choice

In the toric code, a Z-error creates a pair of e (charge) anyons on vertices and an X-error creates a pair of m (flux) anyons on plaquettes. What happens to the state when an e anyon is dragged all the way around an m anyon along a closed loop?

The state is multiplied by the phase i
The e and m anyons annihilate each other into the vacuum
The state is multiplied by -1
The state is left exactly unchanged (multiplied by +1)