There are 3 shapes on a 4x4 grid. Which shape is closest to the yellow 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: yellow trapezoid at (2, 1)
Distance from target shape to red rectangle at (3, 1): 1
Distance from target shape to purple trapezoid at (0, 2): 3
Closest shape is the red rectangle at (3, 1) with distance 1</think>

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