求教为何这道DS题选D？难道是（1）（2）都说明standard dev is zero?

Sophiechinadoll

Web site W receives orders for its products every day. What is the standard deviation of the numbers of orders that Web Site W received daily for the past 5 days?

(1) The average (arithmetic mean) number of orders that Web Site W received per day for the past 5 days is equal to the greatest of the numbers of orders that Web Site W received daily for the past 5 days.

(2) The range of the numbers of orders that Web Site W received daily for the past 5 days is equal to 0.