Does WebSocket support in nginx enable direct client-server communication?

Does WebSocket support in nginx enable direct client-server communication?

I am researching WebSockets and need something clarified: When using
WebSocket support in nginx, with the "Connection Upgrade" technique, which
of the following consequences is true?
A) nginx alleviates the need for a WebSocket "framework" (such as
socket.io, phpwebsockets, etc.), and enables the client to talk directly
to your server scripts without further intermediation.
B) All nginx does is forward the WebSocket traffic, but you still need a
framework (or write your own full native implementation). nginx by no
means "handles" WebSockets as such.