The work of Muzafer Sherif was important for the development of social psychology because he
a. demonstrated the interaction between personality characteristics and situational factors.
b. developed professional associations for social psychologists.
c. showed that complex social behavior could be examined scientifically.
d. helped to find solutions to the crisis in the field during the 1960s and 1970s.

C. showed that complex social behavior could be examined scientifically.                      

Explanation:            

Social Psychology: The term "social psychology" is determined as one of the scientific studies related to different human behaviors in a specific society. It tends to study human beings behavior together in a group and therefore describes the process through which their behavior is being influenced in the presence of others and along with it signifies the "socio-psychological" motives and causes of them in a designated group.

Social psychologists tend to describe that individuals possess an entirely complex social behavior.

A, insurance rates.

Explanation:

The Human Development Index (HDI) assess the development of a country and it is a comparison study among different nations in a particular period of time.

The key dimensions in human development are: a long and healthy life, access to education and a decent standard of living.

The health dimension measures life expectancy at birth, the education one is assessed by years spent at school and in further training facilities, the standard of living is determined by gross national income per capita.