Q has the subject of the sentence “experienced truck drivers”. Hence it will come first. SR is a pair because R talks about the “trucks” mentioned in S. Also, RP is a pair because “the” in R needs to be a followed by a noun, with or without qualifying adjectives. As Q contains the subject and comes first, P is the only option left. Only option B has RP as a pair and Q in the beginning of the sequence.

Hence, B is the correct answer.

We can understand that the sentence is going to be a conditional sentence. Q will come first indicating the beginning of the conditional clause and P will follow Q as “become techniques” and “become get Involved” do not make sense. SR is a pair as they together make the verb of the main clause “will get involved”. Thus QPSR is the appropriate sequence.

Hence, option B is the correct answer.

P is the first fragment because the “so that” is the conjunction of the subordinate clause. RQ is a pair for these two fragments have the pieces of the verb “may live”. S should be put after P, because Q has “too”, which makes it an additional statement. Thus, PSRQ is the most appropriate pair, grammatically and contextually.

Hence, option C is the correct answer.

Q is the only independent fragment and a clause by itself. So it will come first. SP is the pair on the other hand because P completes S. Now, R cannot come at the beginning because it has conjunction “and” that is the joiner of the other clause. So, it is clear that it should be placed after the first independent clause to join it with the second one. Thus, QRSP is the correct sequence.

Hence, option A is the correct answer.

• Only P seems to start independently. Hence it will come first and only option D has P in the beginning.
  
  
• Part R ends with the definite article "the". Thus, it will be followed by a noun. Thus, Q will come after R. 
  
  
• Q ends with the pronoun "that". Thus, it will be followed by a clause, which is given in part S.

Hence, option D is the correct answer.