One import and export company exported his goods under the CIF term. The seller delivered the goods on board the vessel on time and prepared all necessary documents. But the vessel stranded and sank in a few hours after departure. The next day, when the seller asked for payment with full set of documents in conformity with the contract, the buyer refused to accept the documents and rejected payment because his goods have been lost. Is it reasonable for the buyer to do so? ( 是/否 )Why?