WHAT PROCESS TAKES PLACE IN THIS ORGANELLE?

it's the powerhouse of the cell

Explanation:

The mitochondrion is a double-membrane-bound organelle found in most eukaryotic organisms. Some cells in some multicellular organisms lack mitochondria. A number of unicellular organisms, such as microsporidia, parabasalids, and diplomonads, have reduced or transformed their mitochondria into other structures.

the correct option is option d