Which of the following is the best example of a cultural norm?

Question

Which of the following is the best example of a cultural norm? 
        The average height of adults 
        How much respect is given to older people 
        The average year-round temperature 
        The age of the civilization

phil · Answer

how much respect is given to older people

dina · Answer

If I understand the question right, I got this question right. I chose B. It is a behavior of a specific group.

Ms. Sue · Answer

I agree with both of you.

dina · Answer

Thank you both!