In order to strengthen the scientific research cooperation with the cooperation unit, the Shuguang Institute needs to send hard-working scientific and technological personnel to the cooperation unit to work. According to the requirements of the work, the institute's leaders have decided: (1) At least one of the two people must be sent; 2) At most one person can be sent between B and C; (3) If D is sent, both C and E must be sent; (4) At least 5 of A. B, C, D, E Send 3 people. Based on this, can it be launched that will definitely be dispatched? ['B.', 'C.', 'Ding.', 'E.']