Question

an abnormal allele, leading to an abnormal channel protein, is the cause of__________.a hemophiliab cystic fibrosisc unattached earlobesd asthma

Explanation:

Cystic fibrosis is caused by a mutation in the CFTR gene, which encodes a chloride channel protein. When this gene is abnormal, the resulting channel protein is defective. Hemophilia is due to a deficiency in clotting factors (not a channel - protein issue). Unattached earlobes are a simple genetic trait (not a disease caused by a malfunctioning protein in the context of a disease - causing allele as described). Asthma has multiple causes including environmental and genetic factors but not specifically an abnormal channel protein in the way cystic fibrosis does.

Answer:

B. cystic fibrosis