Which one of the following stars is nearest to the Earth?

Answer: (c) Sun

The Sun is a star — the nearest one.

The idea

A star is a body that produces energy through nuclear fusion. The Sun belongs to this same class even though it appears much larger and brighter from Earth. “Nearest star” and “nearest star beyond the Sun” therefore ask different questions.

Why the others are wrong

(a) Polaris is ~430 light-years away.

(b) Alpha Centauri is the nearest star system after the Sun (~4.4 ly).

(d) Sirius is the brightest night star (~8.6 ly).

The trap

Alpha Centauri is the textbook “nearest star” — after the Sun.

Elimination technique

The wording does not exclude the Sun. Recognising it as a star settles the distance comparison without memorising the other stars’ distances.

Also know

Proxima Centauri is the nearest star beyond the Sun, about 4.24 light-years away, and belongs to the Alpha Centauri system. Sirius is the brightest star in the night sky as seen from Earth. Apparent brightness depends on both a star’s own light output and its distance.