Hitler became chancellor of Germany because President Paul von Hindenburg appointed him.
The Khmer Rouge took Cambodia in a bitter civil war with dire consequences.
The similarities are invisible.
The correct answer is - Large numbers of migratory birds;
The number of the migratory birds has always been pretty high and it hadn't resulted in the drying up of the Ogallala Aquifer, not to mention that those birds can not even reach that water because it is underground. Also, the number of the migratory birds have been steadily lowering, so even if they were using that water for drinking, it wouldn't have caused the drying out.
The Ogallala Aquifer has started to dry out because of numerous reasons, with the usage of its water for irrigation being the prime reason. The droughts have become longer, and the temperatures little higher, while the rainfall slightly smaller, so all of that affected the reserves of water in the aquifer negatively.
There were several immediate stated causes for the U.S. declaration of war: first, a series of trade restrictions, Orders in Council (1807), introduced by Britain to impede American trade with France, a country with which Britain was at war (the U.S. contested these restrictions as illegal under international law); second, the impressment (forced recruitment) of U.S. citizens into the Royal Navy; third, the British military support for American Indians who were offering armed resistance to the expansion of the American frontier to the Northwest. President James Madison and Congress declared what is sometimes referred to as the 2nd War of Independence, the War of 1812.
B is the correct answer.
The Supreme Court hears very few of the cases that are brought to it. The Justices decide amongst themselves which cases they will grant an writ of certiorari to, giving them an audience in front of the court. No other group may tell the Supreme Court what cases to hear.