Answer
The graph has an Euler circuit.
Work Step by Step
According to Euler's theorem, for a connected graph to have at least one Euler path, the number of odd vertices must be either 0 or 2. For a connected graph to have at least one Euler circuit, the number of odd vertices must be 0.
The connected graph has no odd vertices. Therefore, by Euler's theorem, the graph has at least one Euler circuit.