Attempt Number: 4
Error Message: Action not unique compared to other actions chosen from this state before. Choose a new action

Action Reasoning:
To bring us closer to the goal state, I should stack block_b on block_c, as it clears the path for further stacking according to the goal configuration.

New State Description:
Block A is on the table and clear. Block B is on top of block C and clear. Block C is on the table and not clear. Block D is on the table and clear. The hand is empty.

Action Chosen:
stack(block_b, block_c)
