This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fluids and Electrolyte Imbalance, Subject name: Medicine
Trans-tubular potassium gradient (T.T.K.G) in hypokalemia is? 
Select and explain. 
A. <3-4, B. >6-7, C. >9-10, D. >10-15
A: <3-4
Answer: A: <3-4 
Explanation: The expected values of the Trans-tubular potassium gradient (T.T.K.G) are <3-4 in the presence of hypokalemia and >6-7 in the presence of hyperkalemia. TTKG is measured as follows: