Which two statements are true about the protocols that are used for transmitting voice traffic？（）
- ARTP multiplexing is used to keep multiple phone conversations separate
- BRTP provides end-to-end delivery services for voice traffic.
- CUDP is used to ensure a reliable transmission from sender to receiver.
- DRTP is used to provide resource reservation for the voice stream.
- EUDP provides multiplexing of multiple phone conversations.