<prompt> The biologic standard used to test the efficiency of sterilization involves the use ofSpores of Clostridium tetaniStreptococcus pneumoniaeSpores of VibrioMycoplamsa  <response>: Spores of Clostridium tetani is used for Dry Heat; 106 spores are used.For moist heat, Bacillus stearothermophilus are usedReference: Ananthanarayan and Paniker;s Textbook of Microbiology; 10th edition 