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

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