FocusPro, a marketing communications and strategy consulting firm, is assisting a client to understand the effects of promotional offers on consumer purchases. They propose the company consider offering three different versions of a coupon that would be mailed to purchasers. The value of the coupon would be manipulated, and the company could track the return of the coupon and how much money was spent by the purchaser. FocusPro recommends that the coupon offers vary between $1 and $5 and suggests three different versions: $1, $3, and $5. The client would select three groups of consumers to receive the coupon offer and a random process would be utilized to determine which coupon offer a consumer would receive. The research will provide important insights about consumer purchasing habits and which coupon offer would lead to the highest level of sales and coupon redemption. This is an example of ______________ research.