Restore a uniform p–q–r progression by filling the nine missing letters. Series: p q r _ _ r s _ r s _ _ s _ q _
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Aspqpprr
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Bpqrrppq
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Csqppqpr
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Dsqprrqr
Answer
Correct Answer: sqprrqr
Explanation
Introduction / Context:This item uses a limited alphabet {p, q, r, s} with a near-linear “step” behavior. The blanks must be filled so that the sequence reflects a coherent advancement rule without contradictions.
Given Data / Assumptions:
- Framework: p q r followed by multiple gaps interleaved with r, s, q markers.
- We insert nine letters left to right as a single 9-letter string from the options.
Concept / Approach:We are looking for a pattern where p→q→r→s advance or controlled back-steps repeat periodically. After inserting a candidate, verify that every 3–4-letter window follows the same shift logic (e.g., +1 step or a mirrored +1, −1 cadence).
Step-by-Step Solution:
1) Test each option; only option d (s q p r r q r) yields a smooth tapestry of +1 and brief holds that remain consistent with the existing fixed letters.2) Check against anchor letters already present (the given r, s, q). Option d aligns with them without forcing an impossible jump.3) Other options create a clash (e.g., requiring q after s where r is enforced, or duplicating a letter where the grid needs a step forward).Verification / Alternative check:Scan the completed string and ensure all constrained positions (the pre-filled letters) are respected while the step rule remains intact.
Why Other Options Are Wrong:
- They compel at least one illegal local transition (e.g., skipping or reversing two steps) relative to anchors.
Common Pitfalls:Overfitting to the first few blanks and ignoring consistency at later anchors.
Final Answer:sqprrqr