What are the following precaution should be take while constructing house in river area?
The construction site of river area should also be far away from quarries (at rivers) as repeated blasting may cause cracks in the building. The building site should be at a reasonably higher level from ground and building should not be more than two storeys.
Above details clears all of the above precautions should be taken while constructing a house in the river area. Thus the correct option is D. Other options are irrelevant.