What is the English multiple-choice question about now?

Scientists believe that Native Americans came to the American continent 10000 years ago through the land bridge connecting Siberia and Alaska today. Alaska now is a noun clause in the sentence. What is the subject in the clause? Alaska is a predicative. What is now+noun can be regarded as a fixed usage. That's what it looks like today. If Alaska is ahead, you can write: Alaska is what it is now.