Which of the following attentions to Sale by Sample are correct?( )
选项：

A:The sample should represent the average quality of the whole lot;
B:The commodity is inadvisable to adopt Sale by Sample when it is difficult to keep the goods in strict accordance with the sample ;
C:More methods are better than one method to stipulate the quality of goods;
D:If the buyer insists on sale by sample or can only provide the buyer’s sample ,the seller can adopt sale by counter sample to transfer from sale by buyer’s sample to sale by seller’s sample;
E:A reference sample should carry the mark clearly showing “For Reference ONLY”, if not ,it is considered as the basis of delivery