Answer:
Red blood.
Step-by-step explanation:
Red blood is for oxygenated blood, while blue blood is for deoxygenated blood.
The blood in Isabelle's left ventricle would be red, in other words, oxygenated. The left ventricle has oxygenated blood because this blood was first in the right ventricle. Then, it went to the pulmonary arteries, which led the blood to the capillaries close to the alveoli in the lungs. In this area, the deoxygenated blood dropped the CO₂ and took O₂ becoming oxygenated blood. Now, this blood is color-coded red and will go to the pulmonary venules, then to the pulmonary vein, and from there, it will go to the left atrium. Lastly, it will go to the left ventricle to start the systemic circulation, which is the one that distributes the oxygenated blood in the body.