I think it is B I apologize if I am incorrect
I believe it is a conditional response due to him having his reaction to the injection being the most prevalent thing in his mind about the doctors.
Colonialism is one of the most strategies of a country in growing their economy. Colonies from a mother country colonies a certain country that contains more resources and it would provide the mother country more resources to have than the mother country would produce. By means of this the economical status of mother country will rise drastically.