_________ is the second nearest star from the Earth.

Students must first understand how distance is computed before looking at astronomers' surveys to determine which star, after the sun, is closest to the earth.
Astronomers employ a technique known as star parallax or the trigonometric parallax method to determine the distance of objects in space because we need to understand how the distance in space is determined. Astronomers simply compare an item's apparent motion in space to the motion of another object used as a backdrop in this method to determine how fast the earth is rotating around the sun.

We know that the sun is the star that is closest to the earth, followed by the Alpha Centauri star, which is the second closest star. Furthermore, it is 4.3 light years away from the planet.

Hence, the correct answer is option C.