Answer:
B) Valves closing
Explanation:
A healthy heart makes a lub-dub sound with each beat. This sound comes from the valves shutting on the blood inside the heart. The first sound (the lub) happens when the mitral and tricuspid valves close.
Answer:
<h3>B) spinal cord </h3>
Explanation:
The spinal cord is a complex organization of nerve cells responsible for movement and sensation. It carries signals between the brain and the rest of the body.
Diverticula.........................
