I use multiple options including a Nikkor 105mm f/2.8 micro, the old and wonderful Nikkor 70-180mm micro with the Nikkor 6T closeup lens. I also use the Canon 500D on the Nikkor 70-200 f/2.8 or the Nikkor 28-300. They all work well, though each is a little different. Given its close minimum focus distance, the 200-500 is good for quick captures of butterflies and other larger insects when a quick opportunity pops up.
When in our home gardens shooting flowers, the dedicated macro lenses work quite well and I don’t have to worry about changing lenses. At a botanical garden when I cannot always zoom with my feet, since they object to people stepping in their planted gardens, the 70-180 zoom macro or the 28-300 and the Canon 500D work quite well.
I sometimes use extension tubes, but usually for fixed work on a tripod. They work well but as noted above are finicky. If you can only chhose one, a dedicated macro lens is a good choice in the 105mm orr longer range to give decent working distance! The longer macros can also double as a decent portrait lens.