This topic examines the principle of compulsory registration of trademarks. The trademark owner can allow the other party to use his trademark under certain conditions through a licensing contract while retaining the trademark ownership, so D is wrong. In addition, China used to adopt compulsory registration for medicines and tobacco products for human use. Later, the Trademark Law was amended, and now only the principle of compulsory registration is adopted for tobacco products. Candidates should pay attention to whether the review materials in their hands reflect the newer legislation.