Answer :
The correct answer is C.
Capillaries deliver blood to individual cells; veins generally deliver
oxygen-depleted blood to the heart; arteries generally bring oxygen-rich
blood away from the heart.
That is why the color of the veins is blue, because oxygen depleted blood is much darker than regular blood, so the veins are darker than arteries who have oxygen rich blood.
That is why the color of the veins is blue, because oxygen depleted blood is much darker than regular blood, so the veins are darker than arteries who have oxygen rich blood.