According to Consumer Protection Principles,when Should Your Business Not Provide

According to consumer protection principles,when should your business not provide a refund for a completed online transaction?

A) when the customer had no opportunity to correct or cancel their order before it was accepted
B) when the transaction was the result of a keystroke error
C) when the customer has entered into the transaction without adequate information
D) when the customer mistakenly entered into the transaction because of inaccurate prompts on your website
E) when the customer has received the ordered goods,kept the goods for several months without complaint,paid the purchase price,and the online contract has been performed by you,yet the customer suddenly demands a refund without any articulated reason