A 62 year – old man with an upper gastrointestinal bleeding receives during resuscitation of a cardiac arrest, a massive transfussion: 8 packed red blood cells, 4 units of fresh frozen plasma and 1 pool of platelets. One hour later presents paraesthesias in mouth and fingers, tetany and wheezing. An ECG may reveal the following signs:
a) Short QT interval:
b) T wave inversion:
c) Heart block:
d) Prolgonged QRS: