Answer:
Option A, President Eisenhower sent federal troops to, is the right answer.
Step-by-step explanation:
A group of Nine students belonging to the African-American community who enrolled in the Little Rock Central High School in the year 1957 came to be known as the Little Rock Nine. Following their enrollment, there emerged the Little Rock Crisis. This crisis emerged because Orval Faubus, the then Governor of Arkansas, prevented the students to enter in the school of Whites.
Faubus called the Arkansas National Guard to prevent he entry of the students. As soon as the Arkansas National Guard surrounded the school, Dwight D. Eisenhower ordered the army of the United States to send troops to the school to protect the students.