Please point out which of the following statements are right．( )

A．The time of shipment should be stipulated in a clear and flexible way in the L/C
B．The time of shipment should not be stipulated in a clear and flexible way in the L/C
C．If the L/C simply stipulates an expiry date without a shipment date which means these two dates are not the same
D．If the L/C simply stipulates an expiry date without a shipment date which means these two dates are the same