The system variable to maintain InnoDB log buffer size is . . . . . . . .

Solution (By Examveda Team)

This question is about how MySQL's InnoDB storage engine manages its log buffer. This buffer is crucial for transaction safety and data recovery.

InnoDB uses a log buffer to store transaction changes before they are written to the disk. This allows transactions to happen faster because they don't have to wait for the disk write.

The system variable that controls the size of this log buffer is:
innodb_log_buffer_size

Let's look at the options:
* Option A: innodb_log_buffer_size - This is the correct answer. It directly controls the size of the InnoDB log buffer.
* Option B: innodb_buffer_log_size - This option doesn't exist in MySQL.
* Option C: buffer_log_innodb_size - This option doesn't exist in MySQL.
* Option D: log_buffer_innodb_size - This option doesn't exist in MySQL.
Therefore, the answer is Option A: innodb_log_buffer_size.