Which process occurs in the structures that are labeled X?
lactic acid fermentation
alcohol fermentation
glycolysis
Krebs cycle

The process that occurs in the structures marked with X is the Krebs cycle (last option).

Explanation:

The Krebs cycle is a process by which energy in the form of ATP is produced from pyruvate molecules obtained by transformation of glucose, which occurs in the mitochondria, marked with X in the diagram (see image).

The mitochondria is a specialized organelle, whose function is the production of energy within the cell. It has a membrane on the outside that allows the passage of proteins, energetic substrate and ions, and inside it crests are formed where the energetic synthesis takes place.

Learn more:

Krebs cycle link

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.