This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Basics of carbohydrate metabolism, Subject name: Biochemistry
The number of ATPs produced by HMP shunt is 
Select and explain. 
A. Zero, B. One, C. Two, D. Four
A: Zero
Answer: A: Zero 
Explanation: The number of ATPs produced by HMP shunt is zero HMP shunt/ Pentose Phosphate pathway Neither produces nor utilizes ATPs. 2 main products of HMP shunt: NADPH - in the irreversible oxidative phase Ribose-5-phosphate - In Reversible non-oxidative phase Rate limiting enzyme - Glucose-6-phosphate dehydrogenase. Extra Edge: The pathways producing Zero ATPs are: HMP (Hexose Monophosphate Pathway) Uronic Acid Pathway Alpha Oxidation Oxidation of Very Long Chain Fatty Acids (VLCFA) RL Shunt/cycle Synthesis of Ketone Bodies