I’ve never seen sprouts sold like this in Spain, so had to take a photo when I went shopping in the local market with my mother, back in the UK, last week. 
Veg Box Recipes (no relation!) have this to say on the subject of this, perhaps the most traditional of Christmas vegetables:
The Brussels Sprout was originally cultivated in Belgium (hence the name) from cabbages. Generations of school children are still lamenting that event…
don't confuse the narrator 