In which of the following vessels curd cannot be stored?

Curd cannot be stored in vessels made up of all the above-mentioned metals.
Curd consists of lactic acid, and acids react with metals producing salt and hydrogen gas. The reason why curd cannot be kept in metals is that the acid in curd will react with the metal and make the food poisonous, causing health problems. In addition to this, acids have a corrosive nature. Thus acids can corrode metal surfaces.