"description": "This event is sent by the caller's client once it has decided which other client to talk to, by selecting one of multiple possible incoming `m.call.answer` events. Its `selected_party_id` field indicates the answer it's chosen. The `call_id` and `party_id` of the caller is also included. If the callee's client sees a `select_answer` for an answer with party ID other than the one it sent, it ends the call and informs the user the call was answered elsewhere. It does not send any events. Media can start flowing before this event is seen or even sent. Clients that implement previous versions of this specification will ignore this event and behave as they did before.",