Meaning that is displayed by [alternatives --config mta] is what?

Question

The following screen appears when run [alternatives --config mta].

There are 2 programs which provide 'mta'.

  Selection    Command
-----------------------------------------------
 + 1           /usr/sbin/sendmail.postfix
*  2           /usr/sbin/sendmail.sendmail

Enter to keep the current selection[+], or type selection number: 

1. What does asterisk(*) mean?
2. What does plus(+) mean?

Answer 1

The asterisk (`*) indicates the option that the alternatives software believes is "best" and would use if auto mode is selected.