--select-file=INDEX... Set file to download by specifying its index.
You can find the file index using the
--show-files option. Multiple indexes can be
specified by using ',', for example: "3,6".
You can also use '-' to specify a range: "1-5".
',' and '-' can be used together.
When used with the -M option, index may vary
depending on the query(see --metalink-* options).