Which Mutation Is an Example of an Adaptation? ​

Which mutation is an example of an adaptation? ​

A) A mutation results in hairless cats, reducing allergies in humans.
B) A mutation renders an individual immune to HIV infection.
C) A mutation increases the size of tomato plants.
D) A mutation is found to be the cause of Alzheimer's Disease.
E) A mutation results in decreased sperm count in humans. ​