There are 4 shapes on a 6x6 grid. Which shape is closest to the blue 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: blue rectangle at (3, 0)
Distance from target shape to cyan square at (5, 1): 3
Distance from target shape to brown rectangle at (5, 5): 7
Distance from target shape to gray rectangle at (4, 2): 3
Closest shape is the cyan square at (5, 1) with distance 3</think>

<answer>(5, 1)</answer>