This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of nucleic acids, Subject name: Biochemistry
[{'content': 'Rapid method of chromosome identification in intersex is \nSelect and explain. \nA. FISH, B. PCR, C. SSCP, D. Karyotyping', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Fluorescence in situ hybridization(FISH) is a cytogenetic technique that uses fluorescent probes that bind to only those pas of the chromosome with a high degree of sequence complementarity. It was developed by biomedical researchers in the early 1980s and is used to detect and localize the presence or absence of specific DNA sequences on chromosomes.', 'role': 'assistant'}]