Since Salespeople Help Their Prospects Make the Choice to Buy

Since salespeople help their prospects make the choice to buy or not buy a product, it is important for salespeople to understand:

A) the various factors that can influence a buyer's decision.
B) how to encourage customers to experience purchase dissonance.
C) the material taught in advanced psychology classes.
D) all that is involved in the psychological processes a buyer goes through in making a purchase decision.
E) the buyer's general buying needs.