'R' will be the first part of the given sequence as it is in continuation with the previous statement, which is clearly indicated from the word, 'suppose' and gives an example for S1. 'Q' will come next as it takes the point mentioned in the previous statement forward. 'P' will come next as it refers back to the previous statement, which is clear from the words, 'these various things'. 'S' will follow logically as it begins with the conjunction, 'and'. Hence, RQPS is the correct sequence. Thus, option (b) is correct.