In the following question, there are six sentences marked S1, S6, P, Q, R and S. The position of S1 and S6 are fixed. Choose one of the four options given below which would be the most logical sequence of the sentences in the passage. S1. The crowd swelled round the thief. P. Suddenly, he whipped out a knife from under his shirt. Q. The thief stood quiet, his head hung in shame. R. The two young men holding him were scared by the sight of the shining knife. S. They took to their heels. S6. They were followed by the crowd which left the thief alone.