Correct answer is -ii) 0
Reindexing a database can be stopped by resetting the timestamp to 0.You can disable reindexing, but it's worthwhile thinking about what problem you're trying to solve by doing that.
Reindexing only happens if you change index settings, and presumably if you change index settings, you'll want the new settings to take effect. If you frequently change index settings and want to control how much resource goes into reindexing, you can also throttle.Specifies the timestamp of fragments to force a reindex/refragment operation. Click the get current timestamp button to enter the current system timestamp. When you set this parameter to a timestamp and reindex enable is set to true, it causes a reindex and refragment operation on all fragments in the database that have a timestamp equal to or less than the specified timestamp.
Note that if you restore a database that has a timestamp set, if there are fragments in the restored content that are older than the specified content, they will start to reindex as soon as they are restored.