"Their dog eats rice."
Translation:Leur chien mange du riz.
I got 2 options saying ''Leur chien mange du riz'' clicked both and got it wrong :/
Apparently it has been fixed since i got 3 different option, among them "Leur chien mange du riz" which is indeed the right one.
I just got three options, mange, mangent, mangeons. Only the mange option is correct.
Are you sure there were two options with mange?
Rice is considered not countable. Hence you have to use the article "du", rather than "des" which is for countable objects.
"Mange" is third person singular (il), but "mangent" is third person plural (ils). Both are pronounced the same, though.