The Trojan War by Helen and her beauty.A. causesB. is causedC. causedD. was caused

问题补充：

The Trojan War by Helen and her beauty.

A. causes

B. is caused

C. caused

D. was caused

答案：

A. causes

B. is caused

C. caused

(答案→)D. was caused

解析：句意:特洛伊战争是因为Helen和她的美丽而引起的。根据句意可知，这句话是主语the Trojan War 和谓语动词cause 之间构成被动的关系，所以排除A、C；并且我们知道特洛伊战争是很久以前的事情了，故应该用一般过去时，故选D。