In apoptosis, Apaf-1 is activated by release of which of the following substances from the mitochondria ?

Ans is 'd' i.e., Cytochrome CApoptosis is induced by a cascade of molecular events all of which culminate in the activation of caspases. 'In the cytosol cytochrome C binds to a protein called Apaf I (Apoptosis activating factor - 1) and the complex activates caspase 9'