Based on the way it is written it sounds like the limitiaion is three hooks on an artificial jigging lure.
2. one treble
or
3. up to three singles
or
I think #4 means you could combine 2 and 3 up to a max of three. Instead of having three single or one treble you could have a "burr" with two and and one single. It wouldn't make sense to have number two and three stated and then have number 4 say you could then combine both....that would mean you could have one treble and three singles on one artificial jigging lure but not allowed to have two trebles or six singles.
Another take is that it is so unclear you can basically do what you want. The old ask for forgiveness rather than permission theory!
