Question

The biggest star in the night sky is _____.
A) Rigel
B) Sirius
C) Proxima centauri
D) Betelgeuse

Answer 1

Here we have to examine each of the options one by one to get the answer.
There are almost $100$ brightest stars in the night sky.

Complete step by step solution:
Rigel: Rigel is a blue supergiant, the most brilliant star in the Orion (Hunter) heavenly body. Because of its estimated scale and light, it is relied upon to end one day in a supernova. It likewise has two notable sidekicks, Rigel B and Rigel C.
The star is $870$ light-years from the sun and $47000$ light-years from the sun. It is a variable star (it's clear brightness shifts) and is known to be an Alpha Cygni-type star.

Sirius: The brightest star noticeable from all aspects of the Planet is Sirius in the heavenly body of Canis Major the Greater Dog. Sirius is additionally called the Star of the Dog. Numerous individuals in the Northern Hemisphere discover Sirius in the southeast – south – or southwest at evenings from winter to mid-spring. The February evenings are an ideal chance to see it. It's additionally enjoyable to consider Sirius to be he rises in the east before first light on pre-fall evenings.

Proxima centauri: The star Proxima Centauri is not apparent to the eye, but it is one of the most prominent stars in Earth's sky. This is because it is known to be part of the Alpha Centauri star cluster, the triple cluster, and the closest star system to our sun. Of the three stars in Alpha Centauri, Proxima is considered to be the one that is currently nearest to our sun, $4.22$ light-years distant.

Betelgeuse: Betelgeuse is ordinarily the tenth brightest star in the night sky and, after Rigel, the second brightest star in the heavenly body of Orion. It is a strikingly ruddy semi-ordinary variable star whose obvious size, going somewhere in the range of $+ 0.0$ and $+ 1.6$ , has the biggest range seen by any first-size star. Betelgeuse is the most brilliant star in the night sky at the close infrared frequencies.

Hence option B is correct.

Note:
Here we may be confused between options A and B. But we must remember that Sirius is the brightest star and Rigel is the second brightest.