Which of the following is the best example of an executive order: a. President Bush vetoed a law allowing wiretapping.
b. President Obama proposed. new health care bill to Congress.
c. President Roosevelt was elected to the presidency for four terms.
d. President Eisenhower ordered troops to protect students in Little Rock, Arkansas

D.  President Eisenhower ordered troops to protect students in Little Rock, Arkansas

Explanation:

Executive order refers to a directive issued by the president of United States to manage a certain federal matters. Executive orders tend to be made if the president felt the need to take a quick action without having to wait the law making process through the congress.

Eisenhower's order for the troops to protect students in Little Rock was known as the  Executive Order 10730 . The soldiers were sent to protect black students from angry mob after the school implemented desegregation

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