There are 5 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 (0, 1)
Distance from target shape to green rectangle at (2, 3): 4
Distance from target shape to blue rectangle at (3, 3): 5
Distance from target shape to red square at (1, 3): 3
Distance from target shape to purple right_triangle at (3, 2): 4
Closest shape is the red square at (1, 3) with distance 3</think>

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