Concept:The question tests logical sequencing of sentence parts to form a coherent statement about political legitimacy and challenges.
Explanation:Start with Q: "one of these is that in focussing on the legitimacy of a political" – this introduces the main idea.
Next, S: "regime or system of rule tells us little about the circumstances" – it continues the thought about what legitimacy does not explain.
Then, R: "in which political authority is challenged as a result" – this specifies the circumstances: situations where authority is challenged.
Finally, P: "of unpopular policies or a discredited leader or government" – it completes the sentence by listing the causes of the challenge.
The sequence QSRP forms a logical and grammatically correct sentence.
Answer:The correct sequence is Q S R P, which corresponds to option (d). Thus, the answer is D.