‘S’ will be the first part of the given sequence as it begins with the pronoun, 'he' and refers back to the subject in S1. ‘P’ will come next as it contains the word, ‘these’ and refers back to the description mentioned in ‘S’. 'Q' will be next as it sums up the previous statements briefly. ‘R’ will follow logically as it completes the description and further throws light on the subject. Hence, SPQR is the correct sequence. Thus, option (d) is correct.