Update README.md

Signed-off-by: Benjamin Löhden <3964467+loehden@users.noreply.github.com>

README.md

@@ -115,7 +115,7 @@ There are other environment variables if you want to customize various things in
 | `VIRTUAL_HOST: <Custom Hostname>`<br/> *Optional* *Default: $ServerIP*   | What your web server 'virtual host' is, accessing admin through this Hostname/IP allows you to make changes to the whitelist / blacklists in addition to the default 'http://pi.hole/admin/' address
 | `IPv6: <"true"\|"false">`<br/> *Optional* *Default: "true"* | For unraid compatibility, strips out all the IPv6 configuration from DNS/Web services when false.
 | `INTERFACE: <NIC>`<br/> *Advanced/Optional* | The default works fine with our basic example docker run commands.  If you're trying to use DHCP with `--net host` mode then you may have to customize this or DNSMASQ_LISTENING.
-| `DNSMASQ_LISTENING: <local\|all\|NIC>`<br/> *Advanced/Optional* | `local` listens on all local subnets, `all` permits listening on internet origin subnets in addition to local.
+| `DNSMASQ_LISTENING: <local\|all\|single>`<br/> *Advanced/Optional* | `local` listens on all local subnets, `all` permits listening on internet origin subnets in addition to local, `single` listens only on the interface specified.
 | `WEB_PORT: <PORT>`<br/> *Advanced/Optional* | **This will break the 'webpage blocked' functionality of Pi-hole** however it may help advanced setups like those running synology or `--net=host` docker argument.  This guide explains how to restore webpage blocked functionality using a linux router DNAT rule: [Alternative Synology installation method](https://discourse.pi-hole.net/t/alternative-synology-installation-method/5454?u=diginc)
 | `DNSMASQ_USER: <pihole\|root>`<br/> *Experimental Default: root* | Allows running FTLDNS as non-root.
 | `TEMPERATUREUNIT`: <c\|k\|f><br/>*Optional Default: c* | Set preferred temperature unit to `c`: Celsius, `k`: Kelvin, or `f` Fahrenheit units.