I find this Danish pronunciation guide very helpful: https://youtu.be/4k6euxk-4Bo. At 2'20", it discusses the word ending "-et". Unlike the indefinite article "et", the word ending "-et" gets a "soft D" (bløde D) sound.
I think "soft D" is the most challenging sound in Danish phonology for a foreigner to master. It is the same sound that we hear at the end of the familiar word "mad" (food). It is often phonetically transcribed using the Old English and Icelandic letter eth "ð", but in the Danish soft-D, the tongue doesn't actually touch the center upper teeth. To foreigners it sounds more like "L", but to Danes these are distinct sounds -- in a soft-D, the tip of the tongue is actually inclined downward, tucked behind the lower teeth. There are several You Tube postings from Native Danish speakers to help us learn to make this sound.
We can consult the forum posting on Danish Alphabet and Sounds https://forum.duolingo.com/comment/4287094/Danish-Alphabet-and-Sounds: Double-K's sound like double-G's, (and double-T's sound like double-D's).
I'm probably too late to answer your question, but I am pretty sure it is. However, it is not the correct answer to this question, because "He is not wearing the clothes" implies that he could still be wearing something else, while "He is not wearing clothes" implies he has nothing on at all.