What letter comes next: B, D, G, K, P, ___?
Correct answer: B. V
The gaps between letters grow by one each time: B→D (+2), D→G (+3), G→K (+4), K→P (+5). The next gap is +6, so P→V. Writing the position numbers (2, 4, 7, 11, 16) makes the growing gaps easy to see.
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