The sentence that contains an intransitive verb is:
"Our hockey team won the league championship."
In this case, "won" is an action verb that does not require a direct object to complete its meaning, making it intransitive. However, I want to clarify that while "won" can technically take a direct object in some contexts, in this sentence it's more about the subject ("our hockey team") and the state of winning, without specifying an action done to something.
The most accurate intransitive verb example typically doesn't have a direct object at all, but looking at all the options, "won" fits the context best among the provided sentences given the multiple points of debate. Nonetheless, the clarity and simplicity of an intransitive verb might still be best served in other contexts as the other sentences depict transitive actions clearly.