There are 3 shapes on a 7x7 grid. Which shape is closest to the green 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: green rectangle at (4, 0)
Distance from target shape to pink square at (0, 4): 8
Distance from target shape to cyan right_triangle at (3, 0): 1
Closest shape is the cyan right_triangle at (3, 0) with distance 1</think>

<answer>(3, 0)</answer>