The box of milk is designed to be square because the square saves more refrigeration space required for storing milk than the round box. In this way, more milk can be placed in a refrigerator. The bottle of Cola is designed to be round because The shape is easier to hold and carry. If the above view is correct, which of the following must be taken as a premise? ['The refrigerated space for milk is smaller than the space for cola.', 'Coke does not need to be refrigerated and milk needs to be refrigerated.', 'Product packaging design is mainly for practical purposes.', 'People cannot accept round milk boxes and square cola bottles.']