The correct sentence where the subject agrees with the verb is:
The team of horses runs across the prairie, startling the sunbathing birds.
In this sentence, "team" is a collective noun treated as a singular subject, which agrees with the singular verb "runs."
The other sentences have mismatched subjects and verbs, as collective nouns like "band," "flock," and "herd" should take singular verbs (roams, scurries, moves) when they refer to the group as a single entity.