Answer:
A
Step-by-step explanation:
sickle cell anamia
Sickle Cell Disease - Causes and Risk Factors | NHLBI, NIH
Sickle Cell Disease - Causes and Risk Factors | NHLBI, NIHSickle cell disease is a genetic disorder caused by mutations in the beta globin gene that leads to faulty hemoglobin protein, called hemoglobin S.