Final answer:
The HTTP status code, such as 200 or 404, is contained within the header part of an HTTP response, which is encapsulated within the payload section of the network frame.
Step-by-step explanation:
The part of a network frame that contains an HTTP status code, such as 200 or 404, is the header. In the context of an HTTP transaction, a frame refers to the data packet that is sent over the network. The HTTP status code is found in the header section of the HTTP response, not the network frame directly, because it is part of the application layer in the OSI model where HTTP operates. The network frame usually pertains to the data link layer or network layer, where different types of information are processed. The HTTP header will be encapsulated within the payload section when we consider the entire network frame traveling through the network.