Final answer:
B) Hematoma. A hematoma is a mass of blood in the tissues that forms when blood vessels rupture. It is caused by an injury or trauma and can occur in various parts of the body.
Step-by-step explanation:
The mass of blood in the tissues is called a hematoma. A hematoma is a localized collection of blood outside the blood vessels, usually caused by an injury or trauma that causes blood vessels to rupture. It forms a solid or semi-solid mass as blood clots within the tissues. Hematomas can occur in different parts of the body, such as the skin, muscles, or organs.