Smith: According to the International Regulations for the Protection of Rare Animals, hybrid animals are not subject to the protection of the Regulations. The objects of protection under the International Regulations for the Protection of Rare Animals include the red wolf. The latest genetic research findings have always been considered The red wolf, which is a purebred species, is actually a cross between a mountain dog and a gray wolf to regain it. Since the red wolf obviously needs protection, the regulations should be amended to make it also protect hybrid animals. Zhang Dazhong: Your opinion cannot be established. Because if the red wolf is indeed a hybrid of a mountain dog and a gray wolf, then even if the existing red wolf is extinct, it can still be retrieved through the cross between the mountain dog and the gray wolf. Which of the following is most likely assumed by Zhang Dazhong's refutation? ['Current techniques for identifying whether an animal is a hybrid are reliable.', 'All existing hybrids are descendants of existing crossbreds.', 'Mountain dogs and gray wolves are purebred species.', 'International Rare Animal Protection Regulations have implemented well.']