Question: Each time MySQL is upgraded, it is best to execute mysql_upgrade, which looks for incompatibilities with the upgraded MySQL server. What does this command do, upon finding a table with a possible incompatibility?

1. it performs a table check and, if problems are found, attempts a table repair.
2. it stops and notifies the server administrator that the upgrade cannot complete until the incompatibility issue are resolved.
3. it provides a full report of the table specifications and the incompatibilities to the server administrator.
4. it performs a table check and, if problems are found, displays the information for the server administrator to take action.

Answer: The correct answer of the above question is Option A:it performs a table check and, if problems are found, attempts a table repair.