This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
QT interval is shoened in- 
Select and explain. 
A. Hypocalcaemia, B. Hypokalemia, C. Hypercalcemia, D. Hyperkalemia
C: Hypercalcemia
Answer: C: Hypercalcemia 
Explanation: only in hypercalcemia QT interval is shoened in the other 3 QT interval is prolonged Hypercalcemia: The most common ECG findings of hypercalcemia are a sho QT interval secondary to a shoened ST segment. There may also be a widened or flattened T wave; however, significant hypercalcemia can cause ECG changes that mimic an acute myocardial infarction. Ref Harrison 20th edition pg 1556