Based on:
According to the provisions of Article 24 of the Patent Law, an invention-creation applying for a patent shall not lose its novelty in any of the following circumstances within six months before the filing date (priority date refers to priority date):
(1) was exhibited for the first time in an international exhibition hosted or recognized by China municipal government;
(2) It was first published at a specific academic conference or technical conference;
(three) without the consent of the applicant, others disclose its contents.
A and D are not right, it should be an "international exhibition". An international exhibition recognized by the China Municipal Government refers to an international exhibition registered or recognized by the Bureau of International Exhibitions as stipulated in the Convention on International Exhibitions. The so-called international exhibition means that besides the products of the host country, there should also be foreign exhibits.