Which tunnel ventilation is provided when the length of the tunnel is large?
- AMechanical ventilationCorrect
- BNatural ventilation
- CBoth (A) and (B)
- DNone of these
Solution
Concept
Mechanical ventilation
Step-by-step solution
1. Long tunnels need mechanical ventilation.
Explanation
Natural ventilation is insufficient.
Why the other options are wrong
Others are not adequate.
Shortcut
Long → mechanical.
Correct answer: A) Mechanical ventilation