Step 1: Analyse dialogue P.
The response “Yes” provides less information than required and withholds the actual time. This flouts the Maxim of Quantity.
Step 2: Analyse dialogue Q.
The answer “Fish” is completely irrelevant to the question, thereby flouting the Maxim of Relation.
Step 3: Analyse dialogue R.
The reply is deliberately ambiguous and indirect, violating clarity and straightforwardness, hence flouting the Maxim of Manner.
Step 4: Analyse dialogue S.
The answer is factually questionable and ironic, thus flouting the Maxim of Quality.
Step 5: Conclusion.
The correct matching is P-(iii), Q-(i), R-(ii), S-(iv).