Whose discovery of radium changed the world’s view of the atom? 
 Answer: It was Marie Curie whose discovery of radium changed the world’s view of the atom. Therefore the correct answer is choice C). 
 According to Sigmund Freud, human behavior is? 
 Answer: According to Sigmund Freud, human behaviour is strongly determined by repressed experiences. Therefore the correct answer is choice D). 
 I hope it helps, Regards.