Task: Question Answering
Input (English): Background Paragraph: Some individuals have a specific mutation in the primary sequence of their hemoglobin molecules that causes them to aggregate, resulting in a deformation of their red blood cells. This abnormality is genetic in nature. A person may inherit the gene from one parent and have sickle cell trait (only some of the hemoglobin is hemoglobin S), which is usually not life-threatening. Inheriting the gene from both parents will result in sickle cell disease, which is a very serious condition. 
Story: Doctors studied two groups of patients. Group W which had people with sickle cell disease, and group A which had normal people in it. 
Question: Which group had fewer individuals with a specific mutation in the primary sequence of their hemoglobin molecules?
Output (English): group A.