In the third paragraph, the author use the example of laboring people tending to drink standardized beer to _______.

A．investigate the extent of the demand for luxury goods
B．classify the kinds of luxury goods desired by eighteenth century consumers
C．explain the motivation of eighteenth century consumers to buy luxury goods
D．establish the extent to which the tastes of rich consumers were shaped by the middle classes in eighteenth century England

A．contrast their views on the subject of luxury consumerism in eighteenth century England
B．indicate the inadequacy of historiographical approaches to eighteenth century English history
C．give examples of historians who have helped to establish the fact of growing consumerism in eighteenth century England
D．support the contention that key questions about eighteenth century consumerism remain to be answered