Explanation:

Let’s break down the logic in (343, 98, 21):

- 343 is 7³

- 98 is 7 × 14

- 21 is 7 × 3

- Notice: All have 7 as a factor. But look closer: 98 ÷ 7 = 14, and 21 ÷ 7 = 3.

- Also, 14 ÷ 3 = roughly 4.666… Not an integer relationship, so maybe that's not it.

- Here’s what stands out—the relationship seems to be:

First number is a perfect cube, the second and third are multiples involving the root of the cube, like so.

Let’s check each option:

- Option 1: (217, 72, 18)

217 = 13 × 17 (not a cube)

72 = 8 × 9

18 = 2 × 9

No clear cube or similar pattern.

- Option 2: (1728, 288, 24)

1728 = 12³

288 = 12 × 24

24 = 12 × 2

Pattern matches: Cube, then number times 2, then 12 times 24.

- Option 3: (1331, 242, 33)

1331 = 11³

242 = 11 × 22

33 = 11 × 3

Same pattern as the set—Cube, then 11 × 22, then 11 × 3.

- Option 4: (512, 126, 27)

512 = 8³

126 = 8 × 15.75 (not an integer)

27 = 3³

The middle number breaks the pattern.

So, the right answer is Option 3: (1331, 242, 33).