‘P’ will be the first part of the given sequence as the possessive pronoun ‘his’ is used in relation to ‘Harsten’ as given in S1. ‘R’ will follow next as ‘both plants’ means ‘two banana plants’ as mentioned in ‘P’. ‘S’ will follow next as the transition word ‘but’ shows the change in one of the plants. ‘Q’ will come next as ‘the music’ is used in the context of ‘some music’ in ‘S’. Hence, PRSQ is the correct sequence. Thus, option (c) is correct.