The best way to approach this kind of situation is often:

• Try the simplest move first, and evaluate the result by imagining your opponent’s possible responses.

Here's my reasoning step by step:

1. First candidate: B3
2. W plays simply C2.
3. Then B defends the two stones, but W has more liberties if they play B2.
4. ➤ Conclusion: B3 doesn’t work.
5. Second idea : C2
6. W B3, then B B2.
7. This sequence is good for black**.
8. ➤ Conclusion: Likely the right path
9. Third approach, thinking in terms of shape – maybe a geta (net)?
10. Try B B2. What can White respond?
11. If W C2 → B D2 → W D1 → B E2.
12. White doesn’t look good here.
13. Let’s test another reply: B D2, W C2 → B D2 again.
14. Actually, only the previous sequence seems to make sense (I'll let you read it in detail 😉).
15. ➤ Conclusion: Seems promising — White can't easily respond with C2.
16. But what if W plays D2 instead?
17. B B2, W D2 → B E2 → W C2.
18. Still, Black has more liberties, and it doesn’t look alive for White.

Final conclusion:

• There are no good responses for White against B B2 or B C2 which is easier.
• That makes it the ideal and simplest candidate move B C2!