Which of the Following Statements About Marketing Information Systems Is

Which of the following statements about marketing information systems is true?

A) Marketing information systems are used to gather, access, and analyze data from intracompany sources, while marketing research deals with external sources.
B) Decision support systems allow managers to see how answers to questions might change in different situations.
C) Computerized marketing information systems tend to increase the quantity of information available for decision making but not without some corresponding decrease in quality.
D) The value of decision support systems is limited because the manager can't use them while he is actually making his decisions.
E) All of the above are true statements.