Final answer:
The bolded section of the text reflects the Falling Action, where the main tension starts to resolve, and consequences of earlier events unfold, leading to a closure.
Step-by-step explanation:
The stage of the plot present in the bolded section is Falling Action. This particular part of the narrative typically follows the climax, showcasing the consequences or effects of the main event and leading towards a resolution. In the provided text, after witnessing a humorous and ironic twist involving the coal, the bean, and a tailor, we see the bean's amusing plight being resolved by the tailor sewing him up. This intervention by the tailor begins to wrap up the story, indicating why a bean has a little black stitch in its side, hence it aligns with the falling action of a plot structure.