Concept:Arranging jumbled parts into a coherent sentence using grammatical and logical connections.
Explanation:The sentence fragment Q (Nothing is so easy and) introduces the main idea.
It is followed by P (inviting as the retort of abuse) to complete the comparative phrase “so easy and inviting as…”.
Next, R (and sarcasm but it is a paltry) joins smoothly using the conjunction “and” and then “but” to contrast.
Finally, S (and an unprofitable contest) ends the sentence with a concluding remark.
Thus the correct sequence is Q, P, R, S.
Answer:Option D: QPRS