In response to the move by the governor of Arkansas to block the Little Rock Nine from attending high school, President Eisenhower

In 1957, Arkansas Governor Orval Faubus used the state National Guard to prevent the Little Rock Nine from entering Central High School. President Eisenhower federalized the Arkansas Guard and sent federal troops to protect the students and enforce the court-ordered integration. So A is correct, though more precisely, federal troops escorted the students; Eisenhower did not order the governor’s Guard to do so.

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