There are 4 shapes on a 5x5 grid. Which shape is closest to the blue rectangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: blue rectangle at (0, 3)
Distance from target shape to brown square at (2, 1): 4
Distance from target shape to purple trapezoid at (4, 4): 5
Distance from target shape to red rectangle at (4, 1): 6
Closest shape is the brown square at (2, 1) with distance 4</think>

<answer>(2, 1)</answer>