The Victorian Age, the height of the British Empire, covered the years ______.

A．A meaningless sentence.
B．A well-formed sentence.
C．A nongrammatical sentence.
D．All of the abov

A．to investigate threats to security of the United States that take place within the U.S. borders
B．to stop the spread of communism in Central and South America
C．to protect the president and vice-president
D．to coordinate intelligence operations