Answer:
Your answer will be (a) polder.
A glacial valley cross-sectional shape is a U shape whereas a stream valley is usually a V shape. The U shape comes from the scouring action of the alpine glaciers which carries rocks with it which can abrade the walls of the valley and the glacier occupies the whole valley so scours out such a shape whereas the stream cuts down and water washes in from the sides of the valley into the stream or river creating the V shape.
A. Basins are the landforms that are most likely to have coal, oil and gas deposits. Much of the countries natural gas, oil and coal are deposited in the bottom of basins.
