Advanced Matrix Reasoning Puzzle

Official explanation

The matrix follows several visual rules at the same time. First, the inner symbols cycle in a repeating order: Triangle → Square → Circle → Diamond Looking at the matrix from left to right and top to bottom, the missing inner symbol should be a triangle. Second, the top marks increase across the final row: One mark → Two marks → Three marks So the missing figure must contain three top vertical marks. Third, the lower horizontal marks also follow the progression of the row. In the final position, the figure must contain three lower horizontal marks. Finally, the frame structure in the final row remains an open corner frame on the left and bottom. The missing option must keep that same frame orientation. Only option D satisfies all of these conditions: triangle inside, three top marks, three lower marks, and the correct open-corner frame. Therefore, the correct answer is D.