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
Key glycolytic enzymes 
Select and explain. 
A. Phosphofructokinase, B. Hexokinase, C. Pyruvate kinase, D. All of these
D: All of these
Answer: D: All of these 
Explanation: Hexokinase & 'c' i.e., Pyruvate kinase

Glycolysis is regulated at 3 steps which are irreversible. These reactions are catalyzed by following key enzymes: (1) Ilexolunase and glucokinase, (2) Phosphofructokinase - I, and (3) Pyruvate kinase.