I am not an expert on bikes but I just phoned my friend who owns his own bike shop, he's very good, I asked him the differences between enduro/sport/cross country and he said some of this:
enduro, more for downhill, jumps etc, more travel, good dual suspension.
cross country, more for racing, not as demanding, more shorter travel, either hardtail or not a lot (hardtail means only front suspension, like my bike).
^^ You can do some downhill jumps with a hardtail, just not as serious as a full suspension bike, i've used mine for downhill and it's so much fun, but I don't do anything crazy, I am noob and scared of the biggest jumps, but i'll do bigger jumps as I get better and gain more confidence.
sport he reckons is more of a beginner bike but covers bases of cross country, he said he isn't sure why whatever website you visited had it listed as sport as he hasn't heard of a type called sport before, least not over here, and the Merida catalogue (where I picked my bike from), doesn't have this option either...
Personally, I would go for cross country or enduro, which one depends on what you will use it for more, I imagine cross country to be a faster bike if you want to travel places faster, as those are more for racing, your choice
My bike I picked from official Merida catalogue, then it got delivered to bike shop, my mate built it free of charge I even got £100 discount
Then I collected it and cycle home with it
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