<prompt> Falsely prolonged QT interval may be a feature of which one of the following conditions?HypokalemiaHyperkalemiaHypocalcemiaHypercalcemia  <response>: Hypokalemia plasma K 3.5 mEqL causes a widened concentration gradient for K inside outside. This results in altered repolarization of ventricles and there would be prominent U wave now, which will immediately follow the T wave. The actual QT interval remains normal 0.4 sec; however, the U wave is erroneously considered a pa of the T wave, and a falsely prolonged QT interval of 0.6 sec is measured. 