Coalition government I think. it was a form of government in which political parties cooperate, reducing the dominance of any one party within that "coalition". The usual reason for this arrangement is so that no party on its own can achieve a majority in the election. A coalition government might also be created in a time of national difficulty or crisis
Dams use hydroelectricity to power towns and cities, so I would go with B) provide power
A slow change such as continents moving will create differences in ecosystems. This is also the same effect caused by a rapid change such a meteorite striking earth. These two phenomena will create diversity and different living conditions. The slow change however, will give organisms time to adopt giving them a good chance of survival unlike a rapid change which will give most, if not all, organisms little chance to survive.
Just like think of what they have in common and what they don't have in common
