【题目】Once the balance of nature __________, natural disasters are likely to strike in ways beyond imagination.
A.is ignored
B.is broken
C.is destroyed
D.is ruined

【答案】B
【解析】ignore意为“忽略”，break意为“破碎，打破”，destroy意为“摧毁”，ruin意为“毁灭”。句意：一旦自然界的平衡遭到破坏，超出人们想象的严重灾害就可能发生。故选break，故答案选B。