Exam SK0-005 topic 1 question 174 discussion

C. DNS (Domain Name System) DNS translates domain names to IP addresses. For a server to authenticate using domain credentials, it must be able to resolve the domain controller's name to an IP address. If DNS settings are incorrect and the server cannot resolve the domain controller's name, it would not be able to authenticate domain accounts, even though it could still ping other servers by their IP addresses. This makes DNS the most likely candidate for the misconfiguration causing the issue.

C. DNS Since the administrator is only able to log on to the server with a local account, it is likely that the server is having difficulty resolving domain names to IP addresses. This suggests that there may be a misconfiguration in the Domain Name System (DNS) settings on the server. DNS is responsible for translating domain names into IP addresses, which allows computers to locate resources on the network. If the DNS settings on the server are incorrect, the server may not be able to locate domain resources, including domain controllers, which would prevent the administrator from logging on with a domain account. DHCP (A) is responsible for assigning IP addresses to devices on the network, and WINS (B) is an older technology used to resolve NetBIOS names to IP addresses. Neither of these services are directly related to logging on to a server with a domain account. TCP (D) is a protocol used to establish connections between devices on a network, and is not likely to be the source of the issue in this scenario.

should D, I think. https://learn.microsoft.com/en-us/troubleshoot/windows-server/identity/cant-sign-the-domain