premise: How to create blue roses<br>Gather the necessary materials. To dye the petals through absorption, you will need powdered blue florist's dye, water, freshly cut white, scissors, dethorning tool (optional), a glass vase, and flower preservative (optional). Ideally, the roses will not have been soaked in or treated with water.
hypothesis: the dethorning tool isn't needed for blue roses.
reason: The dethroning tool is optional! it isn't needed to make blue roses. I think the system overlooked the optional part.