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: Biochemistry
A material that speeds up a chemical reaction without chemically becoming involved is called: 
Select and explain. 
A. A solvent, B. A base, C. A catalyst, D. Thermoplastic
C: A catalyst
Answer: C: A catalyst 
Explanation: None