What is a scoped DNS query?
Solution 1:
Briefly speaking, a scoped DNS query can use only specified network interfaces (e.g. Ethernet or WiFi), while non-scoped can use any available interface.
More verbosely, an application that wants to resolve a name, sends a request (either scoped or non-scoped) to a resolver (usually a DNS client application), if the resolver does not have the answer cached, it sends a DNS query to a particular nameserver (and this goes through one interface, so it is always "scoped").
In your example resolver #1 "for scoped queries" can use only en0 interface (Ethernet).