Answer: The website has a .gov domain name.
Step-by-step explanation:
You are quite correct that D is the answer. When a website has the domain ".gov", it means that it is a government website which makes it credible because the information contained on government websites are official information which means that they have been vetted and approved as the true version of things.
While of course this means that the information contained can be used to manipulate people, it is also the most accurate source of information because the government has considerably more resources than private institutions to find out information on various topics.