Respuesta :

Answer:

veins

Explanation:

Veins carry oxygen-poor (deoxygenated) blood back to the heart, whereas arteries carry oxygen-rich blood away from the heart.

Explanation:

as blood travels through the body, oxygen is used up

and the blood become oxygen poor. oxygen-poor blood returns from the body to the heart through Superior vena cava and inferior vena cava, the two main veins that Bring blood back to the heart. this is my answer