There are 4 shapes on a 4x4 grid. Which shape is closest to the brown trapezoid in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: brown trapezoid at (0, 3)
Distance from target shape to pink rectangle at (3, 1): 5
Distance from target shape to blue right_triangle at (2, 3): 2
Distance from target shape to red rectangle at (1, 3): 1
Closest shape is the red rectangle at (1, 3) with distance 1</think>

<answer>(1, 3)</answer>