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

<answer>(2, 3)</answer>