Concept:
- A statement is guaranteed to be true only if every scenario consistent with the given facts also makes that statement true.
- Test each statement using a counter-example check: try to build one valid scenario that fits all the given facts but still makes the statement false. If such a scenario exists, the statement is not guaranteed.
Step 1: List exactly what the four facts guarantee.
A 3-day festival, a first-time local rock band show, 2000 tickets sold, sale ending next Monday, and 10 weeks of preparation. Nothing here states the venue capacity, the presence of relatives of the performers, or the final tally of tickets sold.
Step 2: Test Statement I, that a few hundred seats will remain empty.
This depends entirely on venue capacity, which is never given. A venue built for exactly 2000 people, or fewer, is fully consistent with the facts and would leave no seats empty, so I is not guaranteed.
Step 3: Test Statement II, that family members of the performers will attend.
Family attendance is never mentioned or implied by any fact. A scenario where not a single relative attends is entirely consistent with the four facts, so II is not guaranteed.
Step 4: Test Statement III, that all tickets will sell out because preparation began 10 weeks earlier.
Preparation time has no logical bearing on ticket demand. A well-organised event can still have unsold tickets on the closing day, and this does not contradict any of the four facts, so III is not guaranteed either.
Step 5: Combine the results.
Since a valid counter-scenario exists for each of I, II, and III individually, none of them follows necessarily from the given facts.
Final Answer: None of them