Step 1: Count the filled dots in each known tile.
Each tile is a 3x3 grid of dots, filled or open, and Panel I arranges 9 such tiles in a 3x3 layout with the last two tiles, middle-right and bottom-right, missing.
Counting the filled dots in each of the 7 known tiles gives, row by row: 8, 1, 6 in row 1; 3, 5 in row 2; 4, 9 in row 3.
Step 2: Spot the number pattern.
The numbers 8, 1, 6 in row 1 add up to 15, and the numbers 4, 9 in row 3 already total 13 with one tile left to find.
These counts are exactly the digits 1 to 9 arranged as the classic 3x3 magic square, where every row, column and diagonal adds up to 15.
Step 3: Solve for the missing counts.
For row 2: \(3 + 5 + x = 15\), so \(x = 7\) filled dots in the middle-right tile.
For row 3: \(4 + 9 + y = 15\), so \(y = 2\) filled dots in the bottom-right tile.
Checking column 3: \(6 + 7 + 2 = 15\), which matches and confirms the pattern is consistent.
Step 4: Match against the options.
Each option in Panel II stacks two tiles, an upper tile for the middle-right position and a lower tile for the bottom-right position.
Only option (i) has an upper tile with exactly 7 filled dots and a lower tile with exactly 2 filled dots; the other options show 6 dots in the upper tile or a different count below.
Final Answer:
Option (i) supplies the missing tiles with dot counts 7 and 2, completing the magic square pattern.
\[ \boxed{\text{Answer} = \text{(i)}} \]