Assertion : Cytochrome c is a small protein attached to the inner surface of the inner mitochondrial membrane. Reason : Complex IV of the electron transport system is the cytochrome bc₁ complex.

Step-by-step solution

Cytochrome c is a small protein attached to the outer surface of the inner mitochondrial membrane. It acts as a mobile carrier for the transfer of electrons between complex III and IV. Thus, the assertion is incorrect. Complex III of the electron transport system is the cytochrome bc₁ complex. Complex IV refers to the cytochrome c oxidase complex containing cytochromes a and a₃ , and two copper centres. Thus, the reason is also incorrect. Both Assertion and Reason are incorrect. Answer: Both Assertion and Reason ar