The correct sequence of increasing bandwidth consumption in the given scenario would be, from lowest to highest:
1. an interactive Telnet session on a server running an SAP application
2. a voice conversation between PC-based VoIP services
3. a voice conversation between two IP phones while accessing an online video site

An interactive Telnet session uses the least amount of bandwidth of the three application examples because it mainly involves the transfer of text.

A voice conversation between IP phones, also known as voice over IP (VoIP) traffic, requires more bandwidth than Telnet. Voice traffic is delay-sensitive and benefits from Quality of Service (QoS) to ensure service quality.

A voice conversation between two IP phones while accessing an online video site would consume the most bandwidth. A voice conversation with real-time video exchange is the equivalent of real-time video traffic. Video traffic is real-time and benefits from dedicated bandwidth with QoS implementation to ensure quality.