There are 4 shapes on a 7x7 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 (5, 0)
Distance from target shape to green trapezoid at (6, 0): 1
Distance from target shape to purple square at (5, 4): 4
Distance from target shape to pink rectangle at (6, 4): 5
Closest shape is the green trapezoid at (6, 0) with distance 1</think>

<answer>(6, 0)</answer>