mysql query to find value which repeats for maximum time

I need to find value in b_id which repeats for maximum time. for example query for the table below should return 40 (n.b., query should return a single value)

| b_id | s_id | doi        | dos        | charge |
+------+------+------------+------------+--------+
|   10 |    3 | 开发者_JS百科0000-00-00 | 0000-00-00 |    200 |
|   10 |    2 | 0000-00-00 | 0000-00-00 |    200 |
|   20 |    1 | 0000-00-00 | 0000-00-00 |    200 |
|   30 |    2 | 0000-00-00 | 0000-00-00 |    200 |
|   40 |    4 | 0000-00-00 | 0000-00-00 |    200 |
|   40 |    5 | 0000-00-00 | 0000-00-00 |    200 |
|   70 |    5 | 0000-00-00 | 0000-00-00 |    200 |
|   40 |    4 | 0000-00-00 | 0000-00-00 |    200 |

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SELECT TOP 1 COUNT(*) as total FROM dbo.Table GROUP BY b_id ORDER BY total DESC

edit: ups, mysql equivalent:

SELECT COUNT(*) as total FROM dbo.Table GROUP BY b_id ORDER BY total DESC LIMIT 1

edit2: after the comment:

SELECT b_id FROM dbo.Table GROUP BY b_id ORDER BY COUNT(b_id) DESC LIMIT 1