None of these
Answer is Right!
Answer is Wrong!
The correct answer is A. 2″.
The minimum depth of space for wheel flange from rail level in BG is 2 inches. This is to ensure that the wheel flange does not come into contact with the rail, which could cause derailment.
The other options are incorrect. Option B is 1.5 inches, which is not enough space for the wheel flange. Option C is 3 inches, which is more space than is required. Option D is none of the above, which is also incorrect.