b选项呢

问题如下：

Which of the following orders are validity instructions?

选项：

A.

Kill or fill orders

B.

Iceberg orders

C.

All or nothing orders

解释：

Kill or fill orders also known as immediate or cancel orders are good only upon receipt by the broker or exchange. If they cannot be filled in part or in whole, they cancel immediately. They are one of the validity instructions.