Answer:
The huntsman advances the plot of the story by arriving at the grandmother's house.
Step-by-step explanation:
Without him arriving, the climax of the story would not have evolved since him getting there meant the discovery of what the wolf had done.
He had been looking for the wolf for a while and he had finally found him.
Through the huntsman's motivations, the story finally concluded with him saving Little Red Riding Hood and her grandmother and killing the wolf in the end.