Which of the Following Statements BEST Describes the Main Purpose

Which of the following statements BEST describes the main purpose of test marketing?

A) To test concept drawings or working models before a focus group of target customers.
B) To test marketing is to test the product itself in real market situations.
C) To test a prototype of the product under laboratory conditions.
D) To allow a select group of target customers to work with pre- release products for use in actual use situations.
E) none of the above