Let's analyze the options:
- Harbhajan Singh: An Indian off-spinner who retired before February 2024, having already reached the milestone much earlier.
- Ravichandran Ashwin: A current Indian off-spinner known for his prowess in Test cricket, a potential candidate for reaching the milestone by 2024.
- Ishant Sharma: A well-known Indian fast bowler but not likely to reach the 500-wicket mark in Tests by February 2024 based on historical performance.
- Mohammed Shami: Another prominent Indian fast bowler but similarly unlikely to have reached 500 Test wickets by the specified time.
Given the above analysis, we focus on contemporary performances and historical progress. Ravichandran Ashwin stands out as the most probable answer due to his exceptional record and continuous presence in Test cricket.
Conclusion: Therefore, Ravichandran Ashwin is the correct answer, having become the second Indian to take 500 wickets in Test matches in February 2024.