John noticed that while on Facebook that The Tiller Nursery had potting soil on sale from it's regular price of $$6\mathrm{.}99$ a bag down to $$3\mathrm{.}99$ a bag. While John was at "The Tiller" he also purchased two azaleas, four box hedges, and a humming bird feeder. You can infer from this information that the nursery used the bags of potting soil as a $\_\_\_\_\_\_\_\_.$

Group of answer choices

Loss leader

Freemium

Bait$-$and$-$switch

Price line

Reference price