This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Biochemistry
[{'content': 'Insulin receptors are \nSelect and explain. \nA. Tyrosine Kinase receptors, B. Phosphodiesterase, C. Calcium calmodulin, D. Lipoprotein', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Insulin receptor is a tyrosine kinase which is heterotetrameric glycoproteinRef: Essentials of Medical Pharmacology, 7th edition, KD Tripathi, page no: 261', 'role': 'assistant'}]