The subject of manners is complex. If it were not, there would not be so many ________ feelings and so much misunderstanding in international communication.
句意： 礼仪是十分复杂的， 否则在国际交流中就不会有那么多感情上的伤害和误解了。 此处需要填形容词来修饰 feelings， 且 feelings 与“伤害” 为被动关系， 故 injured 符合题意。 injurious 有害的。 injury 为名词。 故B 为正确答案。