Among the four alternatives, Raigad alone satisfies the full historical condition. Shivaji was formally crowned at Raigad in 1674, an event that asserted sovereign kingship and supplied ritual legitimacy to the new Maratha state. The distractors need separate rejection: Purandar belongs to a different institution, context or chronology; Sinhagad does not perform the function described in the stem; and Pratapgad fails the required association. The wording of “Shivaji's formal coronation in 1674 took place at which fort?” is deliberately specific, so the candidate should isolate its operative clue before recalling names. — Raigad”, but also remember the factual reason stated above.