Will Mark Brainliest, PLS HELP! Use the image below to answer the question.

The illustration shows the mitochondrial intermembrane space. Molecules enter and exit enzymes. Molecule upper N upper A upper D upper H passes through enzyme upper N upper A upper D upper H Reductase releasing upper H superscript + baseline and upper N upper A upper D superscript + baseline. A blue arrow starts at upper N upper A upper D superscript + and goes through enzyme Ubiquinone then enzyme Cytochrome Reductase, an upper H superscript + baseline is released. The arrow continues through enzyme Cytochrome c and enzyme Cytochrome Oxydase, another upper H superscript + baseline is released. The formula 2 upper H + one-half upper O subscript 2 baseline is to the left of enzyme Cytochrome oxydase with an arrow pointing to the other side. The arrow meets with the arrow from upper N upper A upper D superscript + baseline at upper H subscript 2 baseline upper O. To the right is upper A upper T upper P synthase, upper A upper D upper P + upper P subscript 1 baseline have an arrow going under upper A upper T upper P synthase, an upper H superscript + baseline arrow points to the arrow, the result is upper A upper T upper P.
Which step of cellular respiration is shown in the image?

glycolysis

lactic acid fermentation

electron transport chain

Krebs cycle