This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
[{'content': "'Knudson's two-hit' hypothesis is associated with- \nSelect and explain. \nA. Retinoblastoma, B. Melanoma, C. Ulcerative colitis, D. Crohn's disease", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Harshmohan textbook of pathology 7th edition. Familial retinoblastoma comprises 40% of cases and may be bilateral . In this cases all somatic cells inherit one mutant RBgene from a carrier parent. Later during life the other mutational event of 2nd allele affecting the somatic cells occurs. This forms the basis of two hot hypothesis given by Knudson in 1971..', 'role': 'assistant'}]