Answer:
C - heart attack
Step-by-step explanation:
When the Coronary artery becomes blocked the heart does not get enough oxygen.
Pulmonary vein carries oxygenated blood while pulmonary artery carries deoxygenated blood
The lubb heart sound during diastolic occurs when atrioventricular valve is opening
SA node - AV node - AV bundle
Erythropoietin
Tumours