There are 4 shapes on a 5x5 grid. Which shape is closest to the green square in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: green square at (1, 1)
Distance from target shape to brown square at (1, 4): 3
Distance from target shape to cyan rectangle at (3, 2): 3
Distance from target shape to blue square at (1, 3): 2
Closest shape is the blue square at (1, 3) with distance 2</think>

<answer>(1, 3)</answer>