What is the best lure for lethargic bass?

I have no idea.

A free lined shiner about the length of a credit card and half as tall. Use a flourocarbon leader attached to a 1/0 -2/0 hook and cast 'em gently to the bass.

As for lures, it's tough to say. The bass are shallow, you can see them and they can see you. This and your line may be spooking them into keeping their mouth shut. Try using a flourocarbon leader with your plastics. This may be the ticket.

Finesse Worms (Split Shot or Drop Shot Rig)

try a Drop Shot Rigged Finesse worm. I have had Success with these in shallow water, also.

You might try a 1.5 inch crappie tube jig fished with a slip cork,sometimes a small presentation will work.

I use a rubber frog and tear one of it's legs. Fish will go after the bait that looks injured and vulnerable.

I had the same problem and live crayfish worked. I caught 3 around 18inches or more that day.

this might be a bad answer but buy a cast net

I you should try minnows with a cork, throw it past them and reel it right to them.