Question

Question was provided via image upload.

Explanation:

• Analyze each option:
• "don't undergo systole": Atria do undergo systole (contraction) to pump blood, so this is incorrect.
• "send blood through the aortic and pulmonary semilunar valves": Atria send blood to ventricles, and ventricles send blood through those valves, so this is incorrect.
• "force blood into the ventricles": During atrial systole, atria contract to force blood into ventricles, this is correct.
• "don't produce a diastole": Atria do have diastole (relaxation), so this is incorrect.
• "all of the above": Since other options are incorrect, this is also incorrect.

Answer:

C. force blood into the ventricles.