What Was the Primary Difference Between Marriages of the Upper

What was the primary difference between marriages of the upper and lower classes in Tang-Song China?

A) In the upper classes, males frequently married females of a younger generation.
B) Among members of the lower classes, marriages tended to be consummated at an earlier age than among members of the elite.
C) Members of the elite often married before the age of puberty.
D) Households of the lower classes tended not to be patriarchal.