-A (Aggressive scan options) .
This option enables additional advanced and aggressive options. I haven´t decided exactly which it
stands for yet. Presently this enables OS detection (-O), version scanning (-sV), script scanning
(-sC) and traceroute (--traceroute). More features may be added in the future. The point is to
enable a comprehensive set of scan options without people having to remember a large set of flags.
However, because script scanning with the default set is considered intrusive, you should not use -A
against target networks without permission. This option only enables features, and not timing options
(such as -T4) or verbosity options (-v) that you might want as well.