This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'Malignant change in nevus is characterised by-a)  Darkeningb)  Hemorrhagec)  Itchingd)  Increase in Size \nSelect and explain. \nA. ab, B. cd, C. bd, D. ac', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Warning size of melanoma are : -\n\nItching or pain in a pre-existing mole.\nEnlargement of a pre-existign lesion.\nIrregularity of the borders of a pigmented lesion.\nVariegation of color within a pigmented lesion.\nAssymetry of lesions.', 'role': 'assistant'}]