Nah.A tomato is clearly a vegetable like all the other plant parts. "Vegetables are edible parts of plants that are consumed by humans or other animals as food." All other definitions are just arbitrary and there is no reason why a tomato should not be considered a vegetable.

The definition you cite is also arbitrary, and language changes over time, and over regions.

For what it's worth, I consider tomato a vegetable too, and so, I failed the level initially. Which, to be honest, mirrors my experience with real captchas - I usually have a disagreement with them, regarding what counts as part of the traffic light etc.