Where in the cell does the krebs cycle part of cellular respiration occur ?

In the mitochondrial matrix

Explanation:

The mitochondria is an organelle within the cytoplasm of the cell.  It consists of an outer membrane, inner membrane, and matrix containing a gel-like substance. During aerobic respiration in mitochondria, cells break down sugars in the form of glucose into (carbon dioxide) and   (water) to obtain energy in the form of ATP or adenosine triphosphate.

aerobic respiration:

C6H12O6+ 6 O2        →      6 CO2 + 6 H2O + ≅38 ATP

(glucose)   (oxygen)         (carbon dioxide) + (water)

The Kreb's cycle involves several enzymatic reactions, where pyruvate derivatives obtained from glycolysis, are reduced and oxidized to harvest energy as ATP.

the answer is d.) homologous; have mammary glands