Answer: C
This question mainly assesses the situation in which patent rights are not granted.
The circumstances in which patent rights are not granted include: ① scientific discoveries; ② rules and methods of intellectual activities; ③ methods of diagnosis and treatment of diseases; ④ animal and plant varieties; ⑤ atomic nuclei transformation methods and methods using atomic nuclei transformation Obtained substances; ⑥ Designs made on the patterns, colors, or combination of the two of flat printed matter that mainly serve as a mark. For the production methods of the products listed in item ④, patent rights may be granted in accordance with the provisions of the Patent Law.