Answer:
d. Muscular
Explanation:
Muscular tissue is divided into three major groups: Skeletal Muscle Tissue (large majority of muscles), Heart Muscle Tissue (muscle of the heart) and Smooth Muscle (muscle that involves some organs and tissues).
The heart is an organ made up of muscular tissue. It is the contractile activity of this tissue that gives the heart its role as a blood-pumping organism. Cardiac muscular tissue usually provides a blood supply to other types of tissue.
