There are 3 shapes on a 8x8 grid. Which shape is closest to the red right_triangle 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 right_triangle at (2, 4)
Distance from target shape to cyan rectangle at (4, 0): 6
Distance from target shape to pink rectangle at (2, 5): 1
Closest shape is the pink rectangle at (2, 5) with distance 1</think>

<answer>(2, 5)</answer>