This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Molecular Biology Techniques, Subject name: Biochemistry
All are added to PCR, except: 
Select and explain. 
A. Deoxynucleotide, B. Dideoxynucleotide, C. Thermostat DNAP, D. Template DNA
B: Dideoxynucleotide
Answer: B: Dideoxynucleotide 
Explanation: Ans. B. Dideoxynucleotide(Ref: Tietz Textbook of Clinical Chemistry 4fe page1446)Pre requisites of PCRSample DNA to be amplifiedDeoxynucleotides.Thermostable Polymerase--Taq Polymerase obtained from Thermus Aquaticus found in hot springs.Primer.Mgcl2 , KCl