An optician used concave lens to correct the defect of eye so that the customer can see clearly. Which defect of vision could it be?

An optician used concave lens to correct the defect of eye so that the

1.	An optician used concave lens to correct the defect of eye so that the customer can see clearly. Which defect of vision could it be?
Answer» An optician used concave lens to correct the defect of eye so that the customer can see clearly. Which defect of vision could it be?