Men nu er den død.
Because we are talking about the cat which is common gender. (en kat)
The d is soft in Danish, so is the r - I only knew it was past tense because the lesson is about that. I wonder how difficult it would be to hear the difference in a real conversation. :( Soon to find out, I guess?
Why can't it be "The girl was loving her cat"? For present it could be both present simple and continuous. I see that past simple fits better here, but could it be the other as well?
But this sentence could mean that she might have loved the cat but not anymore or maybe it was dead, meaning she had loved the cat before.