Question

question
which of the following is true of the heart layer indicated in the image below?
answer
it is the inner lining of the serous pericardium, also known as the epicardium.
it contains cardiac muscle tissue.
it lines all chambers and valves.
it is composed of a dense network of collagen fibers that stabilize the position of the heart and associated vessels within the mediastinum.
i dont know yet

Explanation:

The heart has three main layers: epicardium (outer layer, inner lining of serous pericardium), myocardium (middle layer, contains cardiac muscle tissue), and endocardium (inner layer, lines chambers and valves). The description "It contains cardiac muscle tissue" refers to the myocardium.

Answer:

It contains cardiac muscle tissue.