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: Microbiology
[{'content': 'Which one of the components of the TCR (T-cell receptor) is responsible for transmitting signals into the interior of the cell? \nSelect and explain. \nA. Zeta chain, B. Alpha chain, C. Beta chain, D. Gamma chain', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The CD3 complex associated with the TCR receptor contains two zeta chains that function for transmitting intracellular signaling.', 'role': 'assistant'}]