Sales Training Is an Expanding Field

Sales training is an expanding field.Courses are being offered by corporations,commercial vendors,certification studies,and colleges.The main reason for this is because:

A) as new fields of study emerge,it is natural that training will become available in them.
B) sales positions are growing so quickly that demand is outstripping supply.
C) the business community wishes more selling skills among employees.
D) companies want new ways of creating barriers to entry to their lucrative selling positions.
E) we are left wondering since we know that salespeople are born,not trained.