Pick the tunnel which is not a sub-group of traffic tunnels.

In synclinal condition, low pressure areas are found at ______

Folded rocks are often best storehouses of which of water?

Tunnels associated with hydropower generation are called ______

When can the rocks act as a natural arch?

Selection of excavation method depends on ______

Lithology does not affect which parameter?

Geologically, how many classes of tunnels are recognized?