This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
Lens used in Astigmatism: 
Select and explain. 
A. Convex lens, B. Cylindrical, C. Concave lens, D. Contact lens
B: Cylindrical
Answer: B: Cylindrical 
Explanation: Ans. (b) CylindricalRef: A.K. Khurana 6th ed. 142-423* Astigmatism is a common eye condition that's easily corrected by eyeglasses, contact lenses, or surgery.* It is caused by an eye that is not completely round. It is a type of refractive error.* Cause: Astigmatism is a natural and commonly occurring cause of blurred or distorted vision. The exact cause in not known.* Symptom: Blurring of vision which can be associated with fatigue and eyestrain.*The cylindrical lens is used for the management of astigmatism.Also, Know* Myopics are said to be short-sighted. Concave lenses are used in myopics* A convex lens is used in hypermetropic.