In Consumer Behaviour, a Critical Aspect of Household Decision Making

In consumer behaviour, a critical aspect of household decision making is that:

A) the concept is only relevant to people that live in a house with three or more people
B) family purchase decisions are always made by the high- income earner
C) traditional family decision making behaviour has almost become extinct
D) although one person may purchase a product, it can be used by multiple people
E) family preferences for products and services do not change over time