He realized his mistakes and took action to reduce the loss it was too late.A. untilB. w

问题补充：

He realized his mistakes and took action to reduce the loss it was too late.

A. until

B. when

C. before

D. as

答案：

A. until

B. when

(答案→)C. before

D. as

解析：句意：他意识到自己的错误并且采取措施来尽可能地减少损失。before意为“在……之前”，即在太晚之前采取措施；故选C。