The lesser anthropic principle.
Expanding on that a bit: if the Sun were NOT a main sequence star, we wouldn't be around to be asking the question.
The sun is a main sequence star
The sun is actually a main sequence star.
The Sun is a yellow, main sequence star.
the sun is
No. The sun is a main sequence star.
The sun is a main sequence star
main sequence.
The Sun is a yellow, main sequence star.
The sun is a main sequence star, so 1 AU.
The sun is actually a main sequence star.
The Sun is a yellow, main sequence star.
the sun is
No. The sun is a main sequence star.
The sun is a G-type main sequence star.
Because it is on the main sequence. [See related question]
The sun is an average main sequence star.
Main sequence, G2.