What Condition Results from a Single Point Mutation of the Hemoglobin

Multiple Choice

What condition results from a single point mutation of the hemoglobin $\beta$ chain, producing the HbS variant?

A) $\alpha$ -thalassemia
B) $\beta$ -thalassemia
C) hemoglobin SC disease
D) hemolytic anemia
E) sickle-cell anemia