What suggestion does the author make in order to grasp this opportunity

A．find a' way of solving the Denny Doodlebug problem
B．realize how little we know about the complexity of human behavior
C．bring to light codes of some societies which we didn' t know before
D．be aware of the difficulties of communications between different cultures

A．The grammatical rules in the language used by the largest population in a culture.
B．Rules in a culture that can be modeled on by another culture.
C．Any rules that people in a culture receive throughout his lifetime.
D．Rules and codes that shape one's cultural perspective and behavior.