What layer lines the chambers of the heart?Multiple ChoiceEndocardiumMyocardiumEpicardiumPericardium

The layer that lines the chambers of the heart is the Endocardium.

Explanation:

1. Endocardium: This is the innermost layer of the heart, which lines the chambers and is in direct contact with the blood.
2. Myocardium: This is the thick, muscular middle layer responsible for the heart's contractions.
3. Epicardium: This is the outer layer of the heart wall, which also serves as a protective layer.
4. Pericardium: This is a fibrous sac that surrounds the heart, providing protection and anchoring it to surrounding tissues.

In the context of the heart's structure, the endocardium is essential as it creates a smooth lining for blood flow and helps prevent blood clots. Therefore, the correct answer to your question is Endocardium.