Assertion A: When rock conditions are favorable, it will not be necessary to take up concrete lining concurrently with the driving operations till the full length of the tunnel has been driven through rock.
Reason R: A tunnel through rock, hard or soft, does not need any concrete lining
Select your answer

A. Both A and R is true and R is the correct explanation of A

B. Both A and R is true but R is not the correct explanation of A

C. A is true but R is false

D. A is false but R is true

Answer: Option C