You are given the state space shown below, where $A$ is the initial state, and $F$ and $I$ are goal states. The numbers on the edges indicate action costs.

List the order in which uniform search expands states until a solution is found; include initial and goal states. If two nodes have the same $g$ value, the search prefers the one with lexicographically smaller state.
The format of your answer should be as follows (no white spaces): A,C,D