单选题 When a great deal of word processing is carried out, standard letters and documents can be stored at once.
【正确答案】 D
【答案解析】carryout“贯彻、执行、实行” broken；“坏的”；outdated形容词“过时的、落后的”；carry back“拿回、运回”；perform意为“执行、履行”。