Which of the following represents a scenario of potassium cyanide toxicity? -The substrate-level phosphorylation of glucose generates all the ATP required by the cell.
-Chemiosmosis still occurs in the inner mitochondrial membrane and generates all the ATP during cellular respiration.
-Oxidative phosphorylation that generates most of the ATP is blocked, and oxygen cannot accept the electrons from NADH.
-Electrons cannot be transferred from NAD to NADH, and ATP generation from both the substrate level and oxidative phosphorylation is blocked.

Oxidative phosphorylation that generates most of the ATP is blocked, and oxygen cannot accept the electrons from NADH.

Explanation: Sorry this is late and may be wrong but it is my best guess and here is why:

Potassium cyanide blocks the ETC where the majority of ATP is produced. The ETC is a oxidative phosphorylation process where oxygen is needed as the final electron acceptor of NADH.  

The first answer can be eleminated because oxidative phosphorylation produces the most ATP.

The second answer can be eleminated because chemiosmosis does not generate ALL the ATP during cellular respiration, but does produce most of it. Still they worded it as an "all or nothing" type of question so I don't think it is correct.

The fourth answer may not be correct because NAD does not pass on an electron to NADH. Instead, NADH donstes electrons to the ETC and is then turned into NAD. So the process listed is technically backwords.

Sorry I can't be sure about the answer but this is how I broke it down.

cancer   is   essentially   uncontrolled   mitosis   of specialized cells

the most common energy conversion is from kinetic energy to potential energy, and then from potential energy to kinetic energy.

later on comes the heat energy, mechanical energy, and other energy conversions.

this energy conversion is so common that we can find it in our day to day lives as well.

- one of the most common energy conversions involves the changing of potential energy to kinetic energy or kinetic energy to potential energy