Concept:Question tags must agree with the verb and subject of the main clause, and indefinite pronouns like "everybody" take the plural pronoun "they."Explanation:The sentence begins with "Everybody should," which is a positive statement.A positive statement requires a negative question tag.The pronoun "they" replaces "everybody" in the tag because "everybody" refers to a group of people.The auxiliary verb "should" is repeated in the tag.Therefore, the correct tag is "shouldn't they?"Answer:B. shouldn't they