Researchers performed DNA sequencing on parents and their children; they found that the father's age was related to genetic mutations in the children, and the DNA of the children of older fathers had genetic mutations related to autism, schizophrenia, etc. Therefore, the researchers concluded Men need to have children early. The older they are, the higher the child's risk of disease. If the following statement is true, which of the following is the most questionable of this conclusion? ['The older the male, the lower the sperm quality and the more gene mutation fragments are contained.', 'The incidence of autism and schizophrenia is significantly higher in men than in women.', 'Many test couples are similar in age, and the genetic mutations of their children are more likely to come from older mothers.', 'The best childbearing age for men is later than that for women, but the overall childbearing age is significantly longer than for women.']