Examine the labeling and use requirements of drug names and registered trademarks. First, the names of drugs marked in drug instructions and labels must conform to the naming principles of common names of drugs and commodity names published by the state drug supervision and administration department, and be consistent with the corresponding contents of drug approval documents. It can be seen that whether the drug trade name is registered is not the key. Second, it is forbidden to use unregistered trademarks and other drug names that have not been approved by the state drug supervision and administration department in drug instructions and labels. Where a registered trademark is used for a drug label, it shall be printed on the corner of the drug label. It can be seen that registered trademarks can be used. Third, the customary names of drugs published by the national health department can be used when prescribing, and the drug instructions and labels are prohibited because they are not the names of drugs approved by National Medical Products Administration. So the answer is ABC.