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
Enzyme causing covalent bond cleavage without hydrolysis ? 
Select and explain. 
A. Lyase, B. Ligase, C. Hydrolase, D. Transferase
A: Lyase
Answer: A: Lyase 
Explanation: Cleavage by hydrolysis (addition of water) -p Hydrolases
Cleavage without hydrolysis (without addition of water) —> Lyases