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
DNA Amplification is done in 
Select and explain. 
A. PCR, B. NASBA (Nucleic acid sequential based amplification), C. Ligase chain reactions, D. DNA sequencing
A: PCR
Answer: A: PCR 
Explanation: PCR is an in-vitro DNA amplification procedure in which millions of copies of pariticular sequence of DNA can br produced within a few hoursTwo DNA primers about 20-30 nucleotides with complementary sequence of the flanking region can be synthesized