Cyclops is motivated to do this because Odysseus tricked him and humiliated him, and even had the hubris in the end to mess with him about it. Poseidon is the Cyclops' father so naturally the Cyclops wants help and Poseidon can do it because Odysseus is traveling by sea.
I think to explain her understanding, the answer would probably be "find evidence from the text for support".
Si porsupueso por algo se llama commovedora
