What is the name of the blood vessel that carries deoxygenated blood from the body to the heart in a frog?

The correct option is Vena cava.

To understand how blood flows in a frog, we can look at the main components of its circulatory system:
1. The Frog's Heart: Frogs possess a three-chambered heart containing two atria and one ventricle. The right atrium is responsible for receiving deoxygenated blood from the body, while the left atrium receives oxygenated blood from the lungs and skin.
2. Vena Cava: The vena cava (consisting of the anterior and posterior venae cavae) is the primary blood vessel that collects deoxygenated blood from the body tissues and delivers it back to the heart (specifically entering the sinus venosus, which opens into the right atrium).
3. Other Options Explained:
- Aorta: The systemic arches (aortae) carry oxygenated or mixed blood away from the heart to distribute it to the rest of the body.
- Pulmonary artery: Carries deoxygenated blood away from the heart to the lungs for oxygenation.
- Pulmonary vein: Carries oxygenated blood from the lungs back to the left atrium of the heart.