Translate "they read." I answered "wanasoma." I may be a very novice Swahili learner, but I think that's a better response than "wanajifunza," although I can follow how that may work in certain contexts...
I'm pretty sure this is an error; report it.
I reported it Kenny and you are correct.
"Wanajifunza" means "they teach themselves". "Wanasoma" is the correct response in my opinion.