- The sun is a kind of yellow dwarf
- A yellow dwarf is a kind of main sequence star
- So, the sun is a kind of main sequence star

- The sun is a kind of main sequence star
- Alpha mensae is a kind of main sequence star
- So, the sun and alpha mensae are both main sequence star

Therefore, the sun and alpha mensae are both main sequence star
Q: Which of these stars is most similar to the Sun?
Context:
- The sun is a kind of yellow dwarf 
- Alpha mensae is a kind of main sequence star 
- A yellow dwarf is a kind of main sequence star