First you need to identify whether B,C,D in the medical device is also managed by the medical device, according to several categories.
1, B,C,D are not according to the management of medical devices, then A as a whole to obtain a registration certificate can be;
2, if B belongs to the second class of medical devices, C belongs to the third class of medical devices, D does not belong to the medical device, then the A must be in accordance with the third class of medical devices to declare. If B or D is produced by your organization, your organization can declare the registration certificate separately depending on the situation, and you can declare 1 registration certificate with A. If B or D is purchased for your unit, the supplier should be audited to ensure that B or D have a registration certificate.