There are 4 shapes on a 10x10 grid. Which shape is closest to the gray 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: gray rectangle at (9, 0)
Distance from target shape to green square at (0, 4): 13
Distance from target shape to red trapezoid at (5, 8): 12
Distance from target shape to purple square at (3, 1): 7
Closest shape is the purple square at (3, 1) with distance 7</think>

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