Where does cellular respiration take place?

Assertion $A$: Mitochondria are the powerhouse of the cell.
Reason $R$: The sites for cellular respiration,specifically the $Krebs$ cycle and oxidative phosphorylation,are located within the mitochondria.
Which option is correct for Assertion $A$ and Reason $R$?

The "power house" of a cell is ………

Which of the following contains extranuclear genes?

$ATP$ is formed in

Organelles which are regarded as the “Powerhouse of the cell” and in which the oxidative reactions of the respiratory process take place are: