Answer:
A. They fought in segregated units in the armed forces.
The southern colonies (and the colonies in the Caribbeans) required slave labor and indentured servants to maintain plantations that grew valuable crops such as sugar canes and tobacco. Harvesting these crops were often labor intensive that many free workers were unwilling to do without high wages that plantation owners did not wish to pay. These crops could only be grown in the south (or the Caribbean) due to the soil and climate.
Southern state legislatures employed literacy tests as part of the voter registration process starting in the late 19th century. Literacy tests, along with poll taxes, residency and property restrictions and extra-legal activities (violence, intimidation) were all used to deny suffrage to African Americans.
C. USA because of the 3 branches of government.
The British police are called "Bobbies" after Sir Robert (Bobby) Peer, the home Secretary who introduced the act that established the police to the Parliament in 1829. This act proposed to introduce police system instead of the watchmen that had similar responsibilities before.