Question

erythrocytes, leukocytes, and platelets are produced in the:
a bone marrow
b muscles
c liver
d thymus

Explanation:

Erythrocytes (red - blood cells), leukocytes (white - blood cells), and platelets are all formed elements of the blood. Hematopoiesis, the process of blood - cell formation, occurs mainly in the bone marrow. The bone marrow contains hematopoietic stem cells that can differentiate into these various blood cell types. Muscles are for movement and energy - related functions, the liver has functions like detoxification and metabolism, and the thymus is mainly involved in T - cell maturation.

Answer:

A. bone marrow