This paraphrases the stimulus’s main conclusion that florists should stock up on white carnations before St. Patrick’s Day. This is supported by the fact that green carnations are rare and therefore hard to get, while white carnations are cheap and easy to dye to meet the demand.

This is a minor premise in the florist’s argument. It supports the sub-conclusion that green carnations are difficult to produce by explaining that their rarity makes them hard for plant breeders to grow in large quantities.

This references the stimulus’s context. This sentence explains the link between green carnations and St. Patrick’s Day, preparing us to understand why the author suggests that florists should stock up on white carnations, which are cheap and easy to dye green, before the holiday.

This is a major premise. It directly supports the main conclusion by explaining that white carnations are a good choice for meeting the demand for green carnations because they are easy to dye and relatively inexpensive, making it a wise decision for florists to stock up on them.

Though "thus" suggests a conclusion, this sentence is a sub-conclusion of the argument, not the main conclusion. The claim that green carnations are hard to produce supports the main conclusion that florists should stock up on cheaper white carnations before St. Patrick’s Day.