What is the name of the destructive force that breaks down rock?

What was the most difficult obstacle to overcome in the creation of an autonomous state after indian independence was achieved? a british willingness to go to war to retain the region b. religious differences between hindus and muslims c. ethnic differences between tribal regions d. indian princes' inability to decide on a format of government

The action of eventually a low island to form. a. wind b. waves c. volcanoes d. tectonic plates

Identify the youngest layer in the figure ( have to click one letter)