I would go with the last one unless their followers are your target market. In which case you have bigger problems.

You can look at your stats to see where viewers of your most popular stories are coming from. If there aren't a lot coming from "External views" then the blurb is sort of worthless, since your readers are already Medium subscribers.

I did a brief Google ad on one of my Magicland stories just to try to generate a little interest in the novel and the side effect was a few memberships, and I didn't even have a blurb at the time. So that paid for the ad. I wasn't even thinking about that happening.