Sentence 1: Ben returned his books to the library. 
 Sentence 3: He argued that what books were turned in on time 
 Sentence 4:  She decided not to change her mind 
 Sentence 5:  As a result, Ben left regardless what she said 
 Option 1: He decided to go to a different library from now on. 
 Option 2: However, the clerk told him that he owes them $20 dollars.