This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genetics And Genetic Disorders, Subject name: Pediatrics
[{'content': '% of offsprings affected by colour blindness, of a healthy male and heterozygous female: \nSelect and explain. \nA. None, B. 25%, C. 50%, D. 100%', 'role': 'user'}, {'content': "Answer: B \nExplanation: b. 25%(Ref: Nelson's 20/e p 642; Ghai 8/e p 641)Color blindness is an X-linked recessive disorder.In X-linked disorders, if father is normal and mother is a carrier, 50% of children will inherit defective X chromosome.Out of these, the daughters (having 1 normal and 1 defective X chromosome) will act as carriersWhile, all sons, inheriting the defective X chromosome will be affected by colour blindness. Hence, 25% of children will be affected.", 'role': 'assistant'}]