After looking at the ads in her Sunday paper, Ruby decided to visit a local nursery and buy potting soil for her plants at the amazing price of $1.99 a bag. The regular price is $4.99 a bag. While Ruby was there she also purchased three bushes, six flowering plants, and a bird bath. You can infer from this information that the nursery used the bags of potting soil as a

Loss leader

Explanation:

In business, a loss leader is any product or service that is offered to customers for sale below it's market cost, in order to attract customers and stimulate the sales of other additional products or services.

Loss leader pricing strategy is usually used by companies, as they offer a product or service of value to customers below the cost price of the product or service, in order to drive the sales of additional products or services.

From the information given above in the question, we can infer that the nursery used the bags of putting soil as a loss leader, thereby stimulating the sales of additional products such as the three bushes, six flowering plants, and a bird bath that Ruby purchased.