Translation:There is sugar in my tea.
'There is sugar in my tea' sounds very unnatural, like the sugar is there by accident, along the lines of 'There is a fly in my soup ' (a contaminant I did not put there and certainly don't want). I would normally say 'I have sugar in my tea' or even 'I take sugar with my tea' to express this in English.
Just because it is a literal translation doesn't mean it is natural English. It may be grammatically correct, but that doesn't mean a native speaker would actually say it. If it isn't natural, I don't think it is a very good answer. If you look at the people suggesting this as a possible answer, based on their names, very few seem to be native speakers.
The given answer is a normal way to say it in English . "My tea has sugar" is not very natural. Just because it is a direct translation does not make it natural English. As others have said, "my tea has sugar in it" is OK. We also don't say "the right is ...". Try "the right way to say it is ..."