[calmcoconut]

What changed

• Reworked Chapter 8 multiple-choice distractors to make wrong answers more plausible and harder to eliminate by pattern-matching
• Preserved the intended correct answers and existing explanations
• Focused on replacing obviously irrelevant options with conceptually adjacent alternatives from DDIA topics like replication, MVCC, synchronous replication, deadlocks, and offset/idempotency patterns

Why

The prior distractors were generally good, but several questions had one or two answers that were too obviously unrelated to the concept being tested. This made some items easier to guess without understanding the chapter.

Notes

• No write prompts changed
• No flashcards changed
• Correct indices were updated where option ordering changed
• This PR is intended as a quiz-quality audit pass, not a content expansion