Retrieve option value for a given blog id based on name of option.
If the option does not exist or does not have a value, then the return value will be false. This is useful to check whether you need to install an option and is commonly used during installation of plugin options and to test whether upgrading is required.
If the option was serialized then it will be unserialized when it is returned.
(int) (Required) A blog ID. Can be null to refer to the current blog.
(string) (Required) Name of option to retrieve. Expected to not be SQL-escaped.
(mixed) (Optional) Default value to return if the option does not exist.
Default value: false
(mixed) Value set for the option.