In the first line of an HTTP request, which elements are present?

• A. The request method, the resource path, and the HTTP version
• B. The resource path
• C. The response status line
• D. The Host header

Answer: (C)

The first line of an HTTP request is the request line, and it contains three pieces separated by spaces: the request method (like GET or POST) that indicates the action to perform, the resource path (such as /index.html) that identifies what resource to operate on, and the HTTP version (for example HTTP/1.1) that specifies the protocol version being used. This line is followed by a set of header fields, then a blank line, and optionally a message body. The response status line, in contrast, appears only in responses from the server, not in requests. The Host header is part of the subsequent headers, not the first line. So the correct description of the first line is that it includes the method, the resource path, and the HTTP version, as in an example like "GET /index.html HTTP/1.1".