OG 67-they 指代

67. Congress is debating a bill requiring certain employers provide workers with unpaid leave so as to care for sick or newbom children.

(A)  provide workers with unpaid leave so as to

(B)  to provide workers with unpaid leave so as to

(C)  provide workers with unpaid leave in order that they

(D)  to provide workers with unpaid leave so that they can

(E)   provide workers with unpaid leave and

D. 问此处的they指代是不是有歧义，可以是employers也可以是workers ？

我觉得是有歧义，可这是个effectiveness的错误，不能由此就排除D选项

从句子的逻辑意思来看,they只能指代workers.