There are 4 shapes on a 10x10 grid. Which shape is closest to the red 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: red rectangle at (4, 3)
Distance from target shape to orange right_triangle at (9, 0): 8
Distance from target shape to yellow right_triangle at (7, 6): 6
Distance from target shape to gray square at (4, 8): 5
Closest shape is the gray square at (4, 8) with distance 5</think>

<answer>(4, 8)</answer>