The promotional method that involves delivering free products to pre-selected households is

The promotional method that involves delivering free products to pre-selected households is called home sampling. This is a marketing strategy in which companies offer free product samples to targeted households in order to increase awareness and generate interest in their products. The samples can be delivered via mail, through a door-to-door campaign, or at specific locations such as supermarkets or events. Home sampling is an effective way to allow potential customers to experience the product and get a feel for its quality, taste, or usefulness. This can lead to increased sales and brand loyalty in the long run.