The muscle that pumps blood through the circulatory system:

• A. Cardiac muscle
• B. Stomach muscle
• C. Lung
• D. Lymphatic muscle

Answer: (A)

The heart’s pumping action is powered by cardiac muscle, which is specialized for continuous, rhythmic contractions that propel blood through the circulatory system. Cardiac muscle is involuntary and tightly coordinated via intercalated discs, so the heart beat stays synchronized to move blood efficiently. The stomach’s movements are produced by smooth muscle to mix and propel food, not to circulate blood. The lungs aren’t muscles; they’re organs that work with respiratory muscles to move air, not to pump blood. The term “lymphatic muscle” isn’t a standard muscle type involved in circulating blood, since lymph movement is driven by smooth muscle in lymph vessels, not by the heart.