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: Radiology
[{'content': 'Radio isotopes are used in the following techniques except: \nSelect and explain. \nA. Mass spectroscopy, B. RIA, C. ELISA, D. Sequencing of nucleic acid', 'role': 'user'}, {'content': "Answer: C \nExplanation: C i.e. ELISA Concept: ELISA (Enzyme Linked Inununoabsorbent Assay) is an enzyme based immnoassy; the similar test which uses radioactive isotope in place of enzyme is known as Radioimmunoassay (RIA) So I don't think any need of learning that- Nucleic acid sequencing, mass spectroscopy & RIA are tests using radio isotopes.", 'role': 'assistant'}]