The shirley cothran experiment in which billboard advertising was employed over a period of time to determine the impact on ‘brand awareness’ illustrates the application of in marketing.

Controlled test markets

Explanation:

 The controlled test markets uses the real life based scenarios for evaluating the products potential more carefully and also it helps in providing the marketing data with proper designing.

The main benefits of the controlled test markets is that it is basically inexpensive to use and also we can easily use this test ion the marketing as compared to the standard test.  

 According to the question, the impact on the brand awareness basically illustrate the controlled test in the marketing.

Therefore, Controlled test markets is the correct answer.