āSā will be the first part of the given sequence as it is in contrast to with the given sentence as it tells us about what happened next which is clearly indicated from the words, āThe clerk asked for the sales receipt but after searching his pockets the man replied that he had lost itā. āPā will come next as it further takes the conversation forward and represents the consequences of the information given in the previous sentence, that is, āHe said that free alteration is not possible without a receiptā. āQā will come next as it is in continuation with the previous statements which is indicated from the words, āThe man said, 'Okay. I'd like to return the trousers.' The clerk took them back and returned the moneyā. āRā will follow logically as it is in contrast to the previous statement which is indicated from the words, āThe man pushed the money and saidā. Hence, SPQR is the correct sequence. Thus, option (b) is correct.