The owner or the business managers need to prepare the annual budget. This sentence has a mixed compound subject connected by or
, so the verb agrees with the first singular subject. This sentence has a mixed compound subject connected by or, so the verb agrees with the plural subject that is closer. Both parts of the compound subject are plural, so a plural verb is used. A plural indefinite pronoun comes before the compound subject, so a plural verb is used.
The second choice--this sentence has a subject connected by or, so the verb agrees with whatever subject that's closest to it. "the owner" is singular and "the business managers" is plural, so the verb attaches to "managers."
