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
Force not acting in an enzyme substrate complex: 
Select and explain. 
A. Electrostatic, B. Covalent, C. Van der waals, D. Hydrogen
C: Van der waals
Answer: C: Van der waals 
Explanation: Van der waals force are very weak. So not involved in the formation of enzyme substrate complex. Ref: A Textbook of Science for The Health Professions By Barry G ; Evaluation of Enzyme Inhibitors in Drug Discovery: A Guide for Medicinal Chemists and Pharmacologists By Robe Allen Copeland, Page 23 ; Textbook of Biochemistry By Thomas M.Devlin, 4th Edition, Page 156