单选题 By saying that "observers are waiting for the dominoes to start falling", the author means that ______.

A、 observers are taking a wait-and-see attitude towards the future of euthanasia
B、 there is a possibility of similar bills being passed in the U.S. and Canada
C、 observers are waiting to see the movement end up in failure
D、 the process of the bill taking effect may Finally come to a stop

【正确答案】 B

【答案解析】解析：观察家们等着看多米诺骨牌效应，即一个国家通过了允许安乐死的法律，其他国家也相继效仿。