Which of the following statements is correct regarding consumer buying decisions?

A$.$ Consumers are often unaware of what influences their purchases.

B$.$ A buyer's characteristics such as age and income have little influence on buying decisions.

C$.$ The consumer buying decision process is of little interest to marketers.

D$.$ Marketers are interested in what and where consumers buy, but not how much they buy.

E$.$ The easiest part of studying buying decisions is determining the whys behind consumer buying behavior.