The element of plot in the parenthesis in the fable above is the rising action. Rising action is usually found in the first third of the passage, after the introduction or exposition. In this element of plot, the conflict can be introduced and the characters of the story may be established here. This part can also be full of tension and excitement.
Based on the fable, I think that the element of plot that was emphasized was the falling action. Falling action happens right after the climax and it is where the conflict is resolved and it prepares the reader towards the closure of the story. In this case, the part highlighted was when the mouse saved the lion and thus, was able to repay his debt.
