There are 4 shapes on a 10x10 grid. Which shape is closest to the purple 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: purple rectangle at (6, 4)
Distance from target shape to pink rectangle at (9, 9): 8
Distance from target shape to green trapezoid at (5, 0): 5
Distance from target shape to gray trapezoid at (5, 8): 5
Closest shape is the green trapezoid at (5, 0) with distance 5</think>

<answer>(5, 0)</answer>