题目

Bashert is a gentle, golden dog. In her mind, there is no human problem so big she can't lick(舔) better. When her owner is sad, she licks him to make him happy. When her owner feels upset, she licks him again to encourage him.When I go to camp, I miss Bashert a lot, Bashert's owner Aaron Richards, a 14-year-old boy in the US, told the New York Times.Animals like Bashert play an important part in people's lives. Whether it is a dog, a cat or a goldfish, people always enjoy their companionship(陪伴). But do you know that people also love animals for other reasons?When staying with animals, p向5 mL 0.1 mol·L－1 的KI溶液中滴加5~6滴0.1 mol·L－1 的FeCl3溶液后，再进行下列实验，其中可证明FeCl3溶液和KI溶液的反应是可逆反应的实验是（ ）A．再滴加AgNO3溶液，观察是否有AgI沉淀产生B．加入CCl4振荡后，观察下层液体颜色C．再滴加AgNO3溶液，观察是否有AgCl沉淀产生D．再滴加KSCN溶液，观察是否有血红色