Correct option is B
Cant bar:- A tool used primarily in railways to measure the cant or superelevation of the rails. It
measures the difference in height between the two rails, ensuring proper tilting for safe and efficient train travel.
Cant board: A device used in highway engineering to measure the cross level or superelevation of the road. It helps ensure the road surface is properly inclined for drainage and vehicle stability, especially on curves.
Cow bar: Commonly known as a "bull bar" or "brush guard," this is an attachment fitted to the front of vehicles to protect against collisions with animals or brush. It is not used in measuring superelevation or cross levels in highways.
