It is not a good practice to deceive. I Agree with you hundred percent. I reported it but it seems DL doesn't pay attention. In the fast audio says clearly "la" and the slow audio is supposed to help when we are not sure, not in this case when one hear clearly "la" instead of "una".
This is silly... they take a chocolate cake and they carry a chocolate cake are BOTH correct, and both make sense if you don't know exactly what the speaker is telling you. I wrote "They take the chocolate cake" and it marked me incorrect. I believe it should have said "another correct answer is......."
"Chocolate" is a noun in this sentence. Its gender is masculine. "Al cioccolato" is short for "a il cioccolato." That can be translated as "at the chocolate"--which we would not say in English. But it is not an adjective (something I do not know much about yet). I hope that helps!
Wiktionary gives "wear" as the third definition: https://en.wiktionary.org/wiki/portare#Italian
And PONS gives it as the fourth: https://en.pons.com/translate?q=portare&l=enit&in=it&lf=it
'Fetch' means 'go and get' - which isn't the same as 'take' or 'bring'. I can take a cake to a party; I can bring some cake back home after the party. In both cases, travel is in one direction only (to the party or to home). Neither of those would work with 'fetch', which is 'there and back' (e.g. please fetch me some cake from the kitchen).
I agree that 'take' should be accepted, but it's not quite a synonym: they indicate direction of travel from the speaker's location - 'bring' is towards, or along with, the speaker; 'take' is away from the speaker. I don't know if US English distinguishes between the two as much as UK English does, though.
I believe that it is the context. It's a challenge when learning a language. I once had two German boys asking me if the English sentence "What's up?" meant (a) what is happening? or (b) What is up (in the air)? They had disagreed with each other! But I told them. Best wishes!