OpenSUSE Network :: Name Resolution On Multi-homed Networks Using Dnsmasq?

I have a DNS server (dnsmasq v2.55) at the center of three subnets: x.y.1.0/24, x.y.2.0/24 & x.y.3.0/24. dnsmasq does a grand job of issuing a suitable DNS server address with the DHCP option 6. So, machines on subnet x.y.3.0/24 are told that the DNS server is x.y.3.2, machines on subnet x.y.2.0/24 are told that the DNS server is x.y.2.2 and machines on subnet x.y.1.0/24 are told that the DNS server is at x.y.1.2. Even though the DNS server is the same box (although with three nics).

Now the question is:
How do I make dnsmasq respond similarly to name resolution requests? So that when:
Machines from x.y.3.0/24, ping <name of DNS server> dnsmasq returns x.y.3.2,
Machines from x.y.2.0/24, ping <name of DNS server> dnsmasq returns x.y.2.2, and
Machines from x.y.1.0/24, ping <name of DNS server> dnsmasq returns x.y.1.2.

Currently, the DNS server returns the IP address that is assigned in /etc/host. Which, of course can be changed, but via that mechanism, will always be wrong two out of three cases.