Answer: Checks and balances.
Explanation: The whole point of establishing a system of checks and balances was to prevent one of the branches of government from getting too powerful. In order to prevent this, each branch of government has the power to stop another branch of government in the event that they are abusing their powers. In the executive branch (the president), this includes the ability to veto bills. In the judicial branch (Supreme Court), this includes the power to declare an action unconstitutional. And in the legislative branch (Congress/Senate), they have the power of impeachment.
The fact that the constitution gave too much power to the federal government, and that the rights of the people were not guaranteed in the bill of rights.
B and C.
Interestingly enough, the first telegraph message was by it's inventor himself, Samuel Morse, who sent a message from Washington D.C. to Baltimore, which read, "What hath God wrought?"
Denmark was the first to abolish slavery. In 1792 Denmark bans import of slaves to its West Indies colonies.
The Stamp Act (1765) - Tax on stamps in the colonies, meaning you had to pay a tax every time you wanted to mail something
Quartering Act (1765) - Forced Americans to feed and house British soldiers when needed
Townsend Acts (1767) - Series of various taxes imposed on colonies
Boston Massacre (1770) - Angry mob of colonists harass British soldiers in Boston, soldiers get mad and fire into the crowd. Five people are killed.
Tea Act (1773) - Gave the British East India Company a monopoly on tea in the colonies, allowing the company to raise prices as high as they wanted.
Intolerable Acts (1774) - A series of acts in response to the Boston Tea Party that included closing Boston's port, allowing British soldiers to be tried in England rather than America, and a new and improved Quartering Act.
