On edward t. hall's technical level of culture the rules for cultural and nonverbal behaviors are

a. so important that people get very upset when these rules or behaviors are broken.

b. unknown.

c. openly known.

d. openly known and easily stated by most citizens.

I believe the answer is: D ... openly known and easily stated by most citizens

According to Edward, these rules usually would be introduced by each members of the social group right before they become the member of that social group. Examples of such rules are the employee orientation that companies do for new recruits.