Slavery was abolished in the US in the 19th century.24/30SlaverywasabolishedintheUSinthe19thcentury.institutederadicatedeliminatedrequiredGiải thíchĐáp án A Giải thích: abolished (v) thủ tiêu, bãi bỏ, hủy bỏ >< instituted (v) xây dựng