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: Medicine
Which of the following is/are features of polymerase used in recombinant synthesis: 
Select and explain. 
A. Thermostable, B. Doesn't require primer, C. Unusually active, D. All
A: Thermostable
Answer: A: Thermostable 
Explanation: A i.e. Thermostable,