Psychologists suggest that to cure cruelty

1. It is clear that neither of the books mentioned in the passage

1. 
   achieved considerable success in France
   
2. 
   was based on the official work of its author in America
   
3. 
   could explain the American prison system effectively
   
4. 
   touched the slavery system then in operation in America
   

2. The passage makes it clear that the modern prison system

1. 
   was first established in America
   
2. 
   houses mainly debtors and beggars
   
3. 
   was in operation in England in 1166
   
4. 
   was designed by King Henry II
   

3. It is clear in the passage that the two Frenchmen

1. 
   proved very successful in reforming the French prison service
   
2. 
   were both helpful in bringing an end to the slave trade in Europe
   
3. 
   helped develop the modern prison system that concentrated on reforming prisoners
   

D) were not the only Europeans dispatched to America to look at their prison system