There are 3 shapes on a 9x9 grid. Which shape is closest to the yellow 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: yellow square at (5, 5)
Distance from target shape to gray right_triangle at (3, 4): 3
Distance from target shape to brown right_triangle at (6, 8): 4
Closest shape is the gray right_triangle at (3, 4) with distance 3</think>

<answer>(3, 4)</answer>