Concept:The correct sequence arranges the parts logically, starting with the subject “the Constitution” and then following the grammatical structure of the sentence.Explanation:Part (R) “the Constitution lays down certain” introduces the subject and main verb.This is followed by part (P) “directive principles of state policy which though not justiciable are” – this completes what the Constitution lays down.Next is part (Q) “fundamental to the governance of the country and it is the duty” – it continues the description of the directive principles.Finally, part (S) “of the state to apply these principles in making laws” ends the sentence logically.Thus the correct order is RPQS.Answer:Option (c) RPQS