Sentence 1: The scientist needed to find a vaccine for the virus. 
 Sentence 3: He tried multiple concoctions and experiments 
 Sentence 4:  Then, he stumbled upon a cure 
 Sentence 5:  The scientist's hard work was able to help save many lives 
 Option 1: None of it made much sense to him. 
 Option 2: He studied the past work of his peers.