Which of Following Is a Likely Problem for a Manager

Which of following is a likely problem for a manager who uses sales as a measure of advertising effectiveness?

A) Sales results offer little guidance or direction to those responsible for planning and developing the advertising program.
B) There is a short,often immeasurable,time period between when advertising is run and when sales actually occur.
C) Sales results are affected by no marketing mix variable other than price and promotion.
D) No internal environmental variables have any significant influence on sales results.
E) With the correctly selected promotion variables,no external environmental variables have any significant influence on sales results.