S1: Politeness is not a quality possessed by only one nation or race. P: One may observe that a man of one nation will remove his hat or fold his hands by way of greetings when he meets someone he knows. Q: A man of another country will not do so. R: It is a quality to be found among all peoples and nations in every corner of the earth. S: Obviously, each person follows the custom of his particular country. S6: In any case, we should not mock at other’s habits. The Proper sequence should be: A. PRQS B. QPRS C. RPQS D. RPSQ

The correct answer is: D. RPSQ

The first sentence (S1) introduces the topic of the paragraph, which is politeness. The second sentence (P) provides an example of a polite gesture that is common in some cultures but not others. The third sentence (R) states that politeness is a quality that is found in all cultures. The fourth sentence (S) explains that people from different cultures have different customs, and that we should respect these customs. The sixth sentence (S6) concludes the paragraph by stating that we should not mock other people’s habits.

The other options are incorrect because they do not follow the logical order of the sentences. Option A (PRQS) puts the second sentence before the first sentence, which makes no sense. Option B (QPRS) puts the third sentence before the first sentence, which also makes no sense. Option C (RPQS) puts the fourth sentence before the first sentence, which makes no sense.