Natural elimination breeding method: refers to the breeding method to reduce the number of perceived interventions in the selection process of fine varieties and try to determine the required fine varieties through the natural growth being screened. Which of the following are natural breeding methods? ['In order to breed disease-resistant breeding fish, soft-shelled turtles did not use any drugs when the soft-shelled turtles died one after another.', 'Koi fish farmers start to sort the most economical fry from juveniles. After three artificial selections, only about 10% of the juveniles are finally fry.', 'Dendrobium farmers climbed inaccessible cliffs to collect wild Dendrobium, selected some of them as seedlings, and carefully cultivated multiple new varieties.', 'Some plants growing on the hillside, some are very lush, others are weak and yellow, clear and clear. This is exactly the image description of "natural selection".']