Explanation:

Let’s break down the series: 3, 5, 7, 6, 10, 14, 12, 24, 28, 24, 40, 56

Here’s what’s interesting:

- The series actually has two interleaved sequences.

- The odd positions (1st, 3rd, 5th, etc.): 3, 7, 10, 12, 28, 40

- The even positions: 5, 6, 14, 24, 24, 56

- The first sequence (odd positions): 3 ? 7 (+4), 7 ? 10 (+3), 10 ? 12 (+2), 12 ? 28(+16!), 28 ? 40 (+12). The big jump (+16) from 12 to 28 doesn’t fit the previous incremental pattern.

- The second sequence (even positions): 5 ? 6 (+1), 6 ? 14 (+8), 14 ? 24 (+10), 24 ? 24 (zero change), 24 ? 56 (+32). That repeated '24' is suspect.

Let’s check the options:

- Option 1 (10): Fits pattern in odd positions (gradual increases). Seems okay.

- Option 2 (12): Not obviously wrong, matches the mild increase.

- Option 3 (28): That huge leap from 12, then -12 after. Very weird.

- Option 4 (24): On the even side, '24' repeats, which is odd, but mathematically it fits with a jump of 0, if that's the intention. However, a jump of 0 seems less jarring than the jump at '28'.

?? The actual oddball is Option:3, 28. That doesn’t fit the sequence’s logic and symmetry.