Final Answer:
The two circuits by which the gases are circulated in and out of the lungs are Pulmonary circuit and systemic circuit.
Therefore, correct option is (a) Pulmonary circuit and systemic circuit.
Step-by-step explanation:
The two circuits responsible for the circulation of gases in and out of the lungs are the pulmonary circuit and the systemic circuit. In the pulmonary circuit, blood is pumped from the heart to the lungs and back to receive oxygen and release carbon dioxide. The systemic circuit then distributes oxygenated blood to the rest of the body and returns deoxygenated blood to the heart.
The pulmonary circuit specifically involves the movement of blood between the heart and the lungs. Deoxygenated blood is pumped from the heart to the lungs, where it picks up oxygen and releases carbon dioxide.
The oxygenated blood is then transported back to the heart to be pumped into the systemic circuit, providing the body's tissues with oxygen and nutrients.
Therefore, correct option is (a) Pulmonary circuit and systemic circuit.