单选题 Certain animal behaviors, such as mating rituals, seem to be __________ , and therefore external factors such as climate changes, food supply, or the presence of other animals of the same species.
【正确答案】 B
【答案解析】[解析] 形容词词义及动词词组辨析。由题干中的mating rituals(交配仪式)判定此种行为应该是天生的。选项中，unaffected by与后面external factors(外部因素)搭配符合逻辑，故答案为B。