Efficacy means “capacity for producing a desired result or effect” so i believe the answer would be D.
hope this helps!!
Answer:
Heart- Hollow, muscular organ that pumps blood throughout the
body.
Arteries- Blood vessel that carries oxygen-rich blood away from the
heart and to the body parts.
Capillaries- Small blood vessels where materials are exchanged
between the blood and the body's cells (oxygen & carbon
dioxide)
Veins- arries oxygen-poor blood (w/carbon dioxide) back to the
heart (to be pumped out to the lungs)
Explanation:
Try take a picture instead cause we can't see which ones have been italic
