Which statement is not true about simulated test markets?
选项：

A:While a firm's test marketing is in progress, competitors have an opportunity to beat it to the national market.
B:Competitors often take actions such as increasing their promotional efforts to contaminate the test marketing program.
C:Both
D:and
E:are not true about simulated test markets.
F:They yield mathematical estimates of market share based on initial reaction of consumers to a new product.