
Topics:
History of Healthcare Lifestyle Diseases Muscles Human Brain Biology Assessment Tenses Atoms and Radioactivity Dermatosis Ears Psychiatry Vitamin Muscoskeletal System Basic Structure of the Human Body Integumentary System Muscle TissueOther quiz: Biology
the backflow of blood stops in veins by …….
A. valves
B. muscles
C. heartbeats
D. lymphatic vessels