This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: vitamins, Subject name: Biochemistry
[{'content': 'Which of the following vitamin has a role in the regulation of gene expression and tissue differentiation? \nSelect and explain. \nA. Vitamin A, B. Vitamin C, C. Vitamin K, D. Vitamin B12', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Retinoic Acid has a Role in the Regulation of Gene Expression and Tissue Differentiation. A major role of vitamin A is in the control of cell differentiation and turnover. All-trans-retinoic acid and 9-cis-retinoic acid regulate growth, development, and tissue differentiation Like the thyroid and steroid hormones and vitamin D, retinoic acid binds to nuclear receptors that bind to response elements of DNA and regulate the transcription of specific genes Reference: Harper; 30th edition; Page no: 550', 'role': 'assistant'}]