This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.N.S, Subject name: Medicine
Features of parkinsons disease- 
Select and explain. 
A. Decreased Blinking, B. Rigidity, C. On-off phenomenon, D. Objective (downside arrow) muscle power
B: Rigidity
Answer: B: Rigidity 
Explanation: Rigidity is seen in Parkinson's disease. Two types : 1) Cogwheel type, mostly upper limbs(due to tremor superimposed on rigidity) 2) Lead pipe rigidity Rigidity causes stiffness and flexed posture. Ref Harrison20th edition pg 1567