delv(1) on macOS
The text b3a56cdf97eb, as macOS 10.13.6, macOS 10.13.5, macOS 10.13.4 shipped it.
DNS lookup and validation utility
Flags it lists
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-4 -
-6 -
-a -
-b -
-c -
-d -
-h -
-i -
-m -
-p -
-q -
-t -
-v -
-x